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DOE OSTI2020

Materials Data on K2SnBr6 by Materials Project

K2SnBr6 crystallizes in the monoclinic P2 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a body-centered cubic geometry to eight Br1- atoms. There are a spread of K–Br bond distances ranging from 3.50–3.74 Å. In the second K1+ site, K1+ is bonded in a distorted body-centered cubic geometry to eight Br1- atoms. There are a spread of K–Br bond distances ranging from 3.51–3.74 Å. In the third K1+ site, K1+ is bonded in a body-centered cubic geometry to eight Br1- atoms. There are a spread of K–Br bond distances ranging from 3.49–3.74 Å. In the fourth K1+ site, K1+ is bonded in a distorted body-centered cubic geometry to eight Br1- atoms. There are four shorter (3.50 Å) and four longer (3.74 Å) K–Br bond lengths. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded in an octahedral geometry to six Br1- atoms. There are four shorter (2.65 Å) and two longer (2.67 Å) Sn–Br bond lengths. In the second Sn4+ site, Sn4+ is bonded in an octahedral geometry to six Br1- atoms. There are four shorter (2.65 Å) and two longer (2.67 Å) Sn–Br bond lengths. There are eight inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to four K1+ and one Sn4+ atom to form a mixture of distorted edge and corner-sharing BrK4Sn square pyramids. In the second Br1- site, Br1- is bonded to four K1+ and one Sn4+ atom to form a mixture of distorted edge and corner-sharing BrK4Sn square pyramids. In the third Br1- site, Br1- is bonded to four K1+ and one Sn4+ atom to form a mixture of distorted edge and corner-sharing BrK4Sn square pyramids. In the fourth Br1- site, Br1- is bonded to four K1+ and one Sn4+ atom to form a mixture of distorted edge and corner-sharing BrK4Sn square pyramids. In the fifth Br1- site, Br1- is bonded in a distorted trigonal non-coplanar geometry to two K1+ and one Sn4+ atom. In the sixth Br1- site, Br1- is bonded in a distorted trigonal non-coplanar geometry to two K1+ and one Sn4+ atom. In the seventh Br1- site, Br1- is bonded in a distorted trigonal non-coplanar geometry to two K1+ and one Sn4+ atom. In the eighth Br1- site, Br1- is bonded in a distorted trigonal non-coplanar geometry to two K1+ and one Sn4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba2YBr7 by Materials Project

Ba2YBr7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine Br1- atoms. There are a spread of Ba–Br bond distances ranging from 3.24–3.99 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of Ba–Br bond distances ranging from 3.26–3.62 Å. In the third Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine Br1- atoms. There are a spread of Ba–Br bond distances ranging from 3.25–3.95 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine Br1- atoms. There are a spread of Ba–Br bond distances ranging from 3.21–3.95 Å. There are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in an octahedral geometry to six Br1- atoms. There are a spread of Y–Br bond distances ranging from 2.75–2.83 Å. In the second Y3+ site, Y3+ is bonded in an octahedral geometry to six Br1- atoms. There are a spread of Y–Br bond distances ranging from 2.74–2.83 Å. There are fourteen inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 4-coordinate geometry to three Ba2+ and one Y3+ atom. In the second Br1- site, Br1- is bonded in a 1-coordinate geometry to three Ba2+ and one Y3+ atom. In the third Br1- site, Br1- is bonded in a 3-coordinate geometry to two Ba2+ and one Y3+ atom. In the fourth Br1- site, Br1- is bonded in a 3-coordinate geometry to two Ba2+ and one Y3+ atom. In the fifth Br1- site, Br1- is bonded in a 3-coordinate geometry to three Ba2+ and one Y3+ atom. In the sixth Br1- site, Br1- is bonded in a 1-coordinate geometry to two Ba2+ and one Y3+ atom. In the seventh Br1- site, Br1- is bonded in a distorted single-bond geometry to three Ba2+ and one Y3+ atom. In the eighth Br1- site, Br1- is bonded in a 1-coordinate geometry to two Ba2+ and one Y3+ atom. In the ninth Br1- site, Br1- is bonded in a distorted trigonal planar geometry to three Ba2+ atoms. In the tenth Br1- site, Br1- is bonded in a 3-coordinate geometry to three Ba2+ atoms. In the eleventh Br1- site, Br1- is bonded in a 3-coordinate geometry to two Ba2+ and one Y3+ atom. In the twelfth Br1- site, Br1- is bonded in a 2-coordinate geometry to three Ba2+ and one Y3+ atom. In the thirteenth Br1- site, Br1- is bonded in a 1-coordinate geometry to two Ba2+ and one Y3+ atom. In the fourteenth Br1- site, Br1- is bonded in a distorted L-shaped geometry to two Ba2+ and one Y3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba3(BrO)2 by Materials Project

Ba3(OBr)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are six inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to two O2- and three Br1- atoms. There are one shorter (2.47 Å) and one longer (2.49 Å) Ba–O bond lengths. There are a spread of Ba–Br bond distances ranging from 3.30–3.53 Å. In the second Ba2+ site, Ba2+ is bonded in a 3-coordinate geometry to three O2- and three Br1- atoms. There are a spread of Ba–O bond distances ranging from 2.56–2.74 Å. There are a spread of Ba–Br bond distances ranging from 3.46–3.82 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to three O2- and three Br1- atoms. There are a spread of Ba–O bond distances ranging from 2.55–2.66 Å. There are a spread of Ba–Br bond distances ranging from 3.43–3.70 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 3-coordinate geometry to three O2- and three Br1- atoms. There are a spread of Ba–O bond distances ranging from 2.53–2.69 Å. There are a spread of Ba–Br bond distances ranging from 3.50–3.89 Å. In the fifth Ba2+ site, Ba2+ is bonded in a 2-coordinate geometry to two O2- and five Br1- atoms. There are one shorter (2.53 Å) and one longer (2.55 Å) Ba–O bond lengths. There are a spread of Ba–Br bond distances ranging from 3.41–3.84 Å. In the sixth Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to three O2- and three Br1- atoms. There are a spread of Ba–O bond distances ranging from 2.51–2.66 Å. There are one shorter (3.41 Å) and two longer (3.50 Å) Ba–Br bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ba2+ atoms to form a mixture of distorted corner and edge-sharing OBa4 tetrahedra. In the second O2- site, O2- is bonded to four Ba2+ atoms to form a mixture of corner and edge-sharing OBa4 tetrahedra. In the third O2- site, O2- is bonded to four Ba2+ atoms to form a mixture of corner and edge-sharing OBa4 tetrahedra. In the fourth O2- site, O2- is bonded to four Ba2+ atoms to form a mixture of corner and edge-sharing OBa4 tetrahedra. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 5-coordinate geometry to five Ba2+ atoms. In the second Br1- site, Br1- is bonded in a 5-coordinate geometry to five Ba2+ atoms. In the third Br1- site, Br1- is bonded in a distorted pentagonal planar geometry to five Ba2+ atoms. In the fourth Br1- site, Br1- is bonded in a 5-coordinate geometry to five Ba2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3S4Br3 by Materials Project

Re3S4Br3 is Copper structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two Re3S4Br3 clusters. In one of the Re3S4Br3 clusters, there are three inequivalent Re+3.67+ sites. In the first Re+3.67+ site, Re+3.67+ is bonded to four S2- and one Br1- atom to form edge-sharing ReS4Br square pyramids. There are a spread of Re–S bond distances ranging from 2.40–2.47 Å. The Re–Br bond length is 2.52 Å. In the second Re+3.67+ site, Re+3.67+ is bonded to four S2- and one Br1- atom to form edge-sharing ReS4Br square pyramids. There are a spread of Re–S bond distances ranging from 2.42–2.44 Å. The Re–Br bond length is 2.52 Å. In the third Re+3.67+ site, Re+3.67+ is bonded to four S2- and one Br1- atom to form edge-sharing ReS4Br square pyramids. There are a spread of Re–S bond distances ranging from 2.38–2.43 Å. The Re–Br bond length is 2.49 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three Re+3.67+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted single-bond geometry to one Re+3.67+ atom. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Re+3.67+ atom. In the third Br1- site, Br1- is bonded in a single-bond geometry to one Re+3.67+ atom. In one of the Re3S4Br3 clusters, there are three inequivalent Re+3.67+ sites. In the first Re+3.67+ site, Re+3.67+ is bonded to four S2- and one Br1- atom to form edge-sharing ReS4Br square pyramids. There are three shorter (2.40 Å) and one longer (2.41 Å) Re–S bond lengths. The Re–Br bond length is 2.50 Å. In the second Re+3.67+ site, Re+3.67+ is bonded to four S2- and one Br1- atom to form edge-sharing ReS4Br square pyramids. There are a spread of Re–S bond distances ranging from 2.42–2.44 Å. The Re–Br bond length is 2.53 Å. In the third Re+3.67+ site, Re+3.67+ is bonded to four S2- and one Br1- atom to form edge-sharing ReS4Br square pyramids. There are one shorter (2.42 Å) and three longer (2.43 Å) Re–S bond lengths. The Re–Br bond length is 2.51 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three Re+3.67+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to three Re+3.67+ atoms. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted single-bond geometry to one Re+3.67+ atom. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Re+3.67+ atom. In the third Br1- site, Br1- is bonded in a single-bond geometry to one Re+3.67+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te7IrBr7 by Materials Project

IrTe(TeBr)3Te3Br4 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two iridium molecules, two tellurium molecules, two Te3Br4 clusters, and two TeBr clusters. In each Te3Br4 cluster, there are three inequivalent Te+0.57+ sites. In the first Te+0.57+ site, Te+0.57+ is bonded in a single-bond geometry to one Br1- atom. The Te–Br bond length is 3.34 Å. In the second Te+0.57+ site, Te+0.57+ is bonded in a single-bond geometry to one Br1- atom. The Te–Br bond length is 3.13 Å. In the third Te+0.57+ site, Te+0.57+ is bonded in a rectangular see-saw-like geometry to four Br1- atoms. There are a spread of Te–Br bond distances ranging from 2.66–2.94 Å. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted water-like geometry to two Te+0.57+ atoms. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Te+0.57+ atom. In the third Br1- site, Br1- is bonded in a single-bond geometry to one Te+0.57+ atom. In the fourth Br1- site, Br1- is bonded in a 1-coordinate geometry to two Te+0.57+ atoms. In each TeBr cluster, there are three inequivalent Te+0.57+ sites. In the first Te+0.57+ site, Te+0.57+ is bonded in a distorted single-bond geometry to one Br1- atom. The Te–Br bond length is 3.07 Å. In the second Te+0.57+ site, Te+0.57+ is bonded in a distorted single-bond geometry to one Br1- atom. The Te–Br bond length is 3.01 Å. In the third Te+0.57+ site, Te+0.57+ is bonded in a T-shaped geometry to three Br1- atoms. There are a spread of Te–Br bond distances ranging from 2.57–2.82 Å. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in an L-shaped geometry to two Te+0.57+ atoms. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Te+0.57+ atom. In the third Br1- site, Br1- is bonded in a distorted L-shaped geometry to two Te+0.57+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Nd3Br10 by Materials Project

K3Nd3Br10 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of K–Br bond distances ranging from 3.28–3.59 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of K–Br bond distances ranging from 3.28–3.87 Å. In the third K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of K–Br bond distances ranging from 3.30–3.48 Å. There are three inequivalent Nd+2.33+ sites. In the first Nd+2.33+ site, Nd+2.33+ is bonded to seven Br1- atoms to form distorted edge-sharing NdBr7 pentagonal bipyramids. There are a spread of Nd–Br bond distances ranging from 3.00–3.16 Å. In the second Nd+2.33+ site, Nd+2.33+ is bonded to seven Br1- atoms to form distorted edge-sharing NdBr7 pentagonal bipyramids. There are a spread of Nd–Br bond distances ranging from 3.00–3.16 Å. In the third Nd+2.33+ site, Nd+2.33+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of Nd–Br bond distances ranging from 3.03–3.46 Å. There are ten inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 4-coordinate geometry to one K1+ and three Nd+2.33+ atoms. In the second Br1- site, Br1- is bonded to one K1+ and three Nd+2.33+ atoms to form distorted BrKNd3 tetrahedra that share a cornercorner with one BrK3Nd2 square pyramid, corners with two equivalent BrK2Nd2 tetrahedra, corners with five BrK3Nd2 trigonal bipyramids, an edgeedge with one BrK3Nd2 square pyramid, edges with two BrK3Nd2 trigonal bipyramids, and an edgeedge with one BrK2Nd2 trigonal pyramid. In the third Br1- site, Br1- is bonded to two K1+ and two Nd+2.33+ atoms to form distorted BrK2Nd2 tetrahedra that share a cornercorner with one BrK3Nd2 square pyramid, corners with two equivalent BrKNd3 tetrahedra, corners with five BrK3Nd2 trigonal bipyramids, corners with four equivalent BrK2Nd2 trigonal pyramids, an edgeedge with one BrK3Nd2 square pyramid, and edges with two BrK3Nd2 trigonal bipyramids. In the fourth Br1- site, Br1- is bonded to two K1+ and two Nd+2.33+ atoms to form distorted BrK2Nd2 trigonal pyramids that share corners with three equivalent BrK3Nd2 square pyramids, corners with four equivalent BrK2Nd2 tetrahedra, corners with three BrK3Nd2 trigonal bipyramids, an edgeedge with one BrKNd3 tetrahedra, and edges with three BrK3Nd2 trigonal bipyramids. In the fifth Br1- site, Br1- is bonded in a 5-coordinate geometry to three K1+ and two Nd+2.33+ atoms. In the sixth Br1- site, Br1- is bonded in a 5-coordinate geometry to three K1+ and two Nd+2.33+ atoms. In the seventh Br1- site, Br1- is bonded to three K1+ and two Nd+2.33+ atoms to form distorted BrK3Nd2 square pyramids that share corners with two BrKNd3 tetrahedra, corners with four equivalent BrK3Nd2 trigonal bipyramids, corners with three equivalent BrK2Nd2 trigonal pyramids, edges with two BrKNd3 tetrahedra, edges with three BrK3Nd2 trigonal bipyramids, and a faceface with one BrK3Nd2 trigonal bipyramid. In the eighth Br1- site, Br1- is bonded to three K1+ and two Nd+2.33+ atoms to form distorted BrK3Nd2 trigonal bipyramids that share corners with six BrKNd3 tetrahedra, corners with four equivalent BrK3Nd2 trigonal bipyramids, a cornercorner with one BrK2Nd2 trigonal pyramid, edges with two equivalent BrK3Nd2 square pyramids, an edgeedge with one BrK3Nd2 trigonal bipyramid, an edgeedge with one BrK2Nd2 trigonal pyramid, and a faceface with one BrK3Nd2 trigonal bipyramid. In the ninth Br1- site, Br1- is bonded to three K1+ and two Nd+2.33+ atoms to form distorted BrK3Nd2 trigonal bipyramids that share corners with four equivalent BrK3Nd2 square pyramids, corners with two BrKNd3 tetrahedra, corners with four equivalent BrK3Nd2 trigonal bipyramids, a cornercorner with one BrK2Nd2 trigonal pyramid, edges with two BrKNd3 tetrahedra, an edgeedge with one BrK3Nd2 trigonal bipyramid, an edgeedge with one BrK2Nd2 trigonal pyramid, and a faceface with one BrK3Nd2 trigonal bipyramid. In the tenth Br1- site, Br1- is bonded to three K1+ and two Nd+2.33+ atoms to form distorted BrK3Nd2 trigonal bipyramids that share corners with two BrKNd3 tetrahedra, corners with eight BrK3Nd2 trigonal bipyramids, a cornercorner with one BrK2Nd2 trigonal pyramid, an edgeedge with one BrK3Nd2 square pyramid, edges with two BrKNd3 tetrahedra, an edgeedge with one BrK2Nd2 trigonal pyramid, and a faceface with one BrK3Nd2 square pyramid.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Se4Br3 by Materials Project

Re3Se4Br3 is Copper structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two Re3Se4Br3 clusters. In one of the Re3Se4Br3 clusters, there are three inequivalent Re+3.67+ sites. In the first Re+3.67+ site, Re+3.67+ is bonded to four Se2- and one Br1- atom to form edge-sharing ReSe4Br square pyramids. There are a spread of Re–Se bond distances ranging from 2.52–2.63 Å. The Re–Br bond length is 2.55 Å. In the second Re+3.67+ site, Re+3.67+ is bonded to four Se2- and one Br1- atom to form edge-sharing ReSe4Br square pyramids. There are a spread of Re–Se bond distances ranging from 2.53–2.57 Å. The Re–Br bond length is 2.54 Å. In the third Re+3.67+ site, Re+3.67+ is bonded to four Se2- and one Br1- atom to form edge-sharing ReSe4Br square pyramids. There are a spread of Re–Se bond distances ranging from 2.49–2.56 Å. The Re–Br bond length is 2.51 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 9-coordinate geometry to three Re+3.67+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted single-bond geometry to one Re+3.67+ atom. In the second Br1- site, Br1- is bonded in a distorted single-bond geometry to one Re+3.67+ atom. In the third Br1- site, Br1- is bonded in a distorted single-bond geometry to one Re+3.67+ atom. In one of the Re3Se4Br3 clusters, there are three inequivalent Re+3.67+ sites. In the first Re+3.67+ site, Re+3.67+ is bonded to four Se2- and one Br1- atom to form edge-sharing ReSe4Br square pyramids. There are a spread of Re–Se bond distances ranging from 2.49–2.53 Å. The Re–Br bond length is 2.53 Å. In the second Re+3.67+ site, Re+3.67+ is bonded to four Se2- and one Br1- atom to form edge-sharing ReSe4Br square pyramids. There are a spread of Re–Se bond distances ranging from 2.55–2.59 Å. The Re–Br bond length is 2.55 Å. In the third Re+3.67+ site, Re+3.67+ is bonded to four Se2- and one Br1- atom to form edge-sharing ReSe4Br square pyramids. There are a spread of Re–Se bond distances ranging from 2.54–2.59 Å. The Re–Br bond length is 2.54 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the second Se2- site, Se2- is bonded in a 10-coordinate geometry to three Re+3.67+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to three Re+3.67+ atoms. In the fourth Se2- site, Se2- is bonded in a 9-coordinate geometry to three Re+3.67+ atoms. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted single-bond geometry to one Re+3.67+ atom. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Re+3.67+ atom. In the third Br1- site, Br1- is bonded in a single-bond geometry to one Re+3.67+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KPtBr3NO by Materials Project

KPtNOBr3 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 9-coordinate geometry to one N1-, two equivalent O2-, and six Br1- atoms. The K–N bond length is 2.93 Å. Both K–O bond lengths are 2.90 Å. There are a spread of K–Br bond distances ranging from 3.29–3.72 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to two equivalent O2- and six Br1- atoms. There are one shorter (2.90 Å) and one longer (3.23 Å) K–O bond lengths. There are a spread of K–Br bond distances ranging from 3.36–3.75 Å. There are two inequivalent Pt5+ sites. In the first Pt5+ site, Pt5+ is bonded in a square co-planar geometry to one N1- and three Br1- atoms. The Pt–N bond length is 1.75 Å. There are two shorter (2.48 Å) and one longer (2.57 Å) Pt–Br bond lengths. In the second Pt5+ site, Pt5+ is bonded in a 2-coordinate geometry to one N1-, one O2-, and three Br1- atoms. The Pt–N bond length is 1.71 Å. The Pt–O bond length is 1.89 Å. There are a spread of Pt–Br bond distances ranging from 2.53–2.73 Å. There are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a single-bond geometry to one Pt5+ atom. In the second N1- site, N1- is bonded in a distorted linear geometry to one K1+ and one Pt5+ atom. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent K1+ and four equivalent Br1- atoms. There are two shorter (2.86 Å) and two longer (3.07 Å) O–Br bond lengths. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one Pt5+, and one Br1- atom. The O–Br bond length is 2.79 Å. There are five inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 1-coordinate geometry to one K1+ and one Pt5+ atom. In the second Br1- site, Br1- is bonded in a distorted bent 120 degrees geometry to one K1+ and one Pt5+ atom. In the third Br1- site, Br1- is bonded in a 2-coordinate geometry to two K1+ and one Pt5+ atom. In the fourth Br1- site, Br1- is bonded in a 5-coordinate geometry to four equivalent K1+ and one Pt5+ atom. In the fifth Br1- site, Br1- is bonded in a 7-coordinate geometry to three K1+, one Pt5+, and three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg8Br3O4 by Materials Project

HgHgBrHg4O3BrHg2OBr crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four mercury molecules; four Hg2OBr clusters; two HgBr ribbons oriented in the (0, 1, 0) direction; and two Hg4O3Br sheets oriented in the (0, 0, 1) direction. In each Hg2OBr cluster, there are two inequivalent Hg+1.38+ sites. In the first Hg+1.38+ site, Hg+1.38+ is bonded in a 1-coordinate geometry to one Br1- atom. The Hg–Br bond length is 3.10 Å. In the second Hg+1.38+ site, Hg+1.38+ is bonded in a single-bond geometry to one O2- atom. The Hg–O bond length is 2.29 Å. O2- is bonded in a bent 120 degrees geometry to one Hg+1.38+ and one Br1- atom. The O–Br bond length is 1.79 Å. Br1- is bonded in a distorted L-shaped geometry to one Hg+1.38+ and one O2- atom. In each HgBr ribbon, Hg+1.38+ is bonded in a 2-coordinate geometry to one Hg+1.38+ and two equivalent Br1- atoms. The Hg–Hg bond length is 2.63 Å. There are one shorter (2.55 Å) and one longer (3.14 Å) Hg–Br bond lengths. Br1- is bonded in an L-shaped geometry to two equivalent Hg+1.38+ atoms. In each Hg4O3Br sheet, there are four inequivalent Hg+1.38+ sites. In the first Hg+1.38+ site, Hg+1.38+ is bonded in a distorted linear geometry to two O2- and three equivalent Br1- atoms. Both Hg–O bond lengths are 2.11 Å. There are a spread of Hg–Br bond distances ranging from 3.21–3.27 Å. In the second Hg+1.38+ site, Hg+1.38+ is bonded in a 2-coordinate geometry to two O2- and one Br1- atom. Both Hg–O bond lengths are 2.47 Å. The Hg–Br bond length is 3.02 Å. In the third Hg+1.38+ site, Hg+1.38+ is bonded in a distorted single-bond geometry to one O2- atom. The Hg–O bond length is 2.90 Å. In the fourth Hg+1.38+ site, Hg+1.38+ is bonded to three O2- and one Br1- atom to form distorted corner-sharing HgBrO3 trigonal pyramids. There are a spread of Hg–O bond distances ranging from 2.29–2.34 Å. The Hg–Br bond length is 2.92 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four Hg+1.38+ atoms to form corner-sharing OHg4 tetrahedra. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Hg+1.38+ and one O2- atom. The O–O bond length is 1.40 Å. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Hg+1.38+ and one O2- atom. Br1- is bonded in a 5-coordinate geometry to five Hg+1.38+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnHg3Se3Br2 by Materials Project

Hg3ZnSe3Br2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are six inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a square co-planar geometry to two equivalent Se2- and two equivalent Br1- atoms. Both Hg–Se bond lengths are 2.58 Å. Both Hg–Br bond lengths are 3.24 Å. In the second Hg2+ site, Hg2+ is bonded in a square co-planar geometry to two equivalent Se2- and two equivalent Br1- atoms. Both Hg–Se bond lengths are 2.54 Å. Both Hg–Br bond lengths are 3.34 Å. In the third Hg2+ site, Hg2+ is bonded in a distorted square co-planar geometry to four Br1- atoms. There are two shorter (2.48 Å) and two longer (3.25 Å) Hg–Br bond lengths. In the fourth Hg2+ site, Hg2+ is bonded in a distorted linear geometry to two equivalent Se2- and two equivalent Br1- atoms. Both Hg–Se bond lengths are 2.52 Å. Both Hg–Br bond lengths are 3.55 Å. In the fifth Hg2+ site, Hg2+ is bonded to two equivalent Se2- and four Br1- atoms to form distorted HgSe2Br4 octahedra that share corners with two equivalent ZnSe4 tetrahedra. Both Hg–Se bond lengths are 3.30 Å. There are two shorter (2.59 Å) and two longer (3.07 Å) Hg–Br bond lengths. In the sixth Hg2+ site, Hg2+ is bonded in a distorted square co-planar geometry to two equivalent Se2- and two equivalent Br1- atoms. Both Hg–Se bond lengths are 2.54 Å. Both Hg–Br bond lengths are 3.38 Å. Zn2+ is bonded to four Se2- atoms to form ZnSe4 tetrahedra that share a cornercorner with one HgSe2Br4 octahedra and an edgeedge with one ZnSe4 tetrahedra. The corner-sharing octahedral tilt angles are 74°. There are a spread of Zn–Se bond distances ranging from 2.46–2.63 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to one Hg2+ and two equivalent Zn2+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to two Hg2+ and one Zn2+ atom. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to two Hg2+ and one Zn2+ atom. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 1-coordinate geometry to four Hg2+ atoms. In the second Br1- site, Br1- is bonded in a 1-coordinate geometry to four Hg2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlBi2Te2BrCl4 by Materials Project

AlBi2Te2BrCl4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Al3+ is bonded to four Cl1- atoms to form AlCl4 tetrahedra that share a cornercorner with one BiTe3Br2Cl octahedra. The corner-sharing octahedral tilt angles are 77°. There are a spread of Al–Cl bond distances ranging from 2.15–2.17 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to three Te2-, two Br1-, and three Cl1- atoms. There are a spread of Bi–Te bond distances ranging from 3.00–3.02 Å. There are one shorter (3.36 Å) and one longer (3.39 Å) Bi–Br bond lengths. There are a spread of Bi–Cl bond distances ranging from 3.30–3.61 Å. In the second Bi3+ site, Bi3+ is bonded to three Te2-, two Br1-, and one Cl1- atom to form distorted BiTe3Br2Cl octahedra that share a cornercorner with one AlCl4 tetrahedra and edges with two equivalent BiTe3Br2Cl octahedra. There are a spread of Bi–Te bond distances ranging from 3.01–3.03 Å. There are one shorter (3.29 Å) and one longer (3.32 Å) Bi–Br bond lengths. The Bi–Cl bond length is 3.23 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 9-coordinate geometry to three Bi3+, two Br1-, and four Cl1- atoms. There are one shorter (3.75 Å) and one longer (3.77 Å) Te–Br bond lengths. There are a spread of Te–Cl bond distances ranging from 3.66–4.18 Å. In the second Te2- site, Te2- is bonded in a 9-coordinate geometry to three Bi3+, two Br1-, and four Cl1- atoms. There are one shorter (3.83 Å) and one longer (3.85 Å) Te–Br bond lengths. There are a spread of Te–Cl bond distances ranging from 3.97–4.19 Å. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 10-coordinate geometry to four Bi3+, four Te2-, and two equivalent Cl1- atoms. Both Br–Cl bond lengths are 3.61 Å. In the second Br1- site, Br1- is bonded in a 10-coordinate geometry to four Bi3+, four Te2-, and two equivalent Cl1- atoms. Both Br–Cl bond lengths are 3.65 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+, one Bi3+, two Te2-, and one Br1- atom. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Al3+, one Bi3+, and two Te2- atoms. In the third Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Al3+, one Bi3+, and two Te2- atoms. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+, one Bi3+, two Te2-, and one Br1- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba(BrF4)2 by Materials Project

Ba(BrF4)2 crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. there are two inequivalent Ba sites. In the first Ba site, Ba is bonded to twelve F atoms to form distorted corner-sharing BaF12 cuboctahedra. There are a spread of Ba–F bond distances ranging from 2.86–3.13 Å. In the second Ba site, Ba is bonded to eight F atoms to form distorted corner-sharing BaF8 hexagonal bipyramids. There are four shorter (2.71 Å) and four longer (2.78 Å) Ba–F bond lengths. Br is bonded in a rectangular see-saw-like geometry to four F atoms. There are a spread of Br–F bond distances ranging from 1.91–1.97 Å. There are four inequivalent F sites. In the first F site, F is bonded in a bent 150 degrees geometry to one Ba and one Br atom. In the second F site, F is bonded in a bent 120 degrees geometry to one Ba and one Br atom. In the third F site, F is bonded in a 2-coordinate geometry to two Ba and one Br atom. In the fourth F site, F is bonded in a 1-coordinate geometry to one Ba and one Br atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlBi2Se2BrCl4 by Materials Project

AlBi2Se2BrCl4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Al3+ is bonded in a tetrahedral geometry to four Cl1- atoms. There are a spread of Al–Cl bond distances ranging from 2.16–2.18 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to three Se2-, two Br1-, and three Cl1- atoms. There are a spread of Bi–Se bond distances ranging from 2.81–2.83 Å. There are one shorter (3.30 Å) and one longer (3.33 Å) Bi–Br bond lengths. There are a spread of Bi–Cl bond distances ranging from 3.19–3.56 Å. In the second Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to three Se2-, two Br1-, and one Cl1- atom. There are one shorter (2.82 Å) and two longer (2.83 Å) Bi–Se bond lengths. There are one shorter (3.26 Å) and one longer (3.28 Å) Bi–Br bond lengths. The Bi–Cl bond length is 3.17 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three Bi3+ and two Br1- atoms. There are one shorter (3.66 Å) and one longer (3.67 Å) Se–Br bond lengths. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to three Bi3+ and two Br1- atoms. There are one shorter (3.72 Å) and one longer (3.74 Å) Se–Br bond lengths. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 4-coordinate geometry to four Bi3+, four Se2-, and two equivalent Cl1- atoms. Both Br–Cl bond lengths are 3.60 Å. In the second Br1- site, Br1- is bonded in a 4-coordinate geometry to four Bi3+, four Se2-, and two equivalent Cl1- atoms. Both Br–Cl bond lengths are 3.61 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+, one Bi3+, and one Br1- atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+, one Bi3+, and one Br1- atom. In the third Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Al3+ and one Bi3+ atom. In the fourth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Al3+ and one Bi3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na11B21(BrO18)2 by Materials Project

Na11B21(O18Br)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 7-coordinate geometry to six O2- and one Br1- atom. There are a spread of Na–O bond distances ranging from 2.34–2.60 Å. The Na–Br bond length is 3.46 Å. In the second Na1+ site, Na1+ is bonded in a 2-coordinate geometry to seven O2- and one Br1- atom. There are a spread of Na–O bond distances ranging from 2.28–3.17 Å. The Na–Br bond length is 3.32 Å. In the third Na1+ site, Na1+ is bonded in a 7-coordinate geometry to five O2- and two equivalent Br1- atoms. There are a spread of Na–O bond distances ranging from 2.29–3.01 Å. There are one shorter (2.94 Å) and one longer (3.26 Å) Na–Br bond lengths. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to five O2- and one Br1- atom. There are a spread of Na–O bond distances ranging from 2.24–2.94 Å. The Na–Br bond length is 2.89 Å. In the fifth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to six O2- and one Br1- atom. There are a spread of Na–O bond distances ranging from 2.38–2.78 Å. The Na–Br bond length is 3.13 Å. In the sixth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to four O2- and two equivalent Br1- atoms. There are two shorter (2.32 Å) and two longer (2.36 Å) Na–O bond lengths. Both Na–Br bond lengths are 3.35 Å. There are eleven inequivalent B3+ sites. In the first B3+ site, B3+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of B–O bond distances ranging from 1.44–1.50 Å. In the second B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.44–1.52 Å. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.36–1.41 Å. In the fourth B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.50 Å. In the fifth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.36–1.40 Å. In the sixth B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There is two shorter (1.45 Å) and two longer (1.53 Å) B–O bond length. In the seventh B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.37–1.40 Å. In the eighth B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.53 Å. In the ninth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.37 Å) and one longer (1.39 Å) B–O bond length. In the tenth B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.37 Å) and one longer (1.39 Å) B–O bond length. In the eleventh B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.36–1.40 Å. There are nineteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent B3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two B3+ atoms. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+ and two B3+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two B3+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two B3+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Na1+ and two equivalent B3+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Na1+ and two B3+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two B3+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two B3+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two B3+ atoms. In the eleventh O2- site, O2- is bonded in a bent 120 degrees geometry to three Na1+ and two B3+ atoms. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two B3+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Na1+ and two B3+ atoms. In the fourteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two B3+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Na1+ and two B3+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Na1+ and two B3+ atoms. In the seventeenth O2- site, O2- is bonded in a bent 120 degrees geometry to one Na1+ and two B3+ atoms. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+ and two B3+ atoms. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two B3+ atoms. Br1- is bonded in a 7-coordinate geometry to seven Na1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Strong mutual increase in the efficiency of isotope-selective laser IR dissociation of molecules under nonequilibrium thermodynamic conditions of the compression shock under irradiation in a bimolecular mixture

We have revealed a strong (by a factor of 2 to 5) mutual increase in the yield of IR molecular dissociation (by the example of CF{sub 2}HCl and CF{sub 3}Br) and a significant (by a factor of 1.5 to 3) lowering of dissociation thresholds in the nonequilibrium thermodynamic conditions of compression shock in the irradiation of the molecules by resonance IR laser radiation in the bimolecular mixture in comparison with their individual irradiation. This opens up the possibility to perform efficient isotope-selective IR dissociation of molecules at lower excitation energy densities (Φ ⩽ 1.5 – 2.0 J cm{sup −2}) and thereby to improve the dissociation selectivity. This was demonstrated by the example of chlorine- and bromine-isotope selective dissociation of the specified molecules, which are characterised by quite small (less than 0.25 cm{sup −1}) isotope shifts in the IR vibrational absorption spectra excited by laser radiation. The enrichment coefficients K {sub enr}({sup 35}Cl / {sup 37}Cl) = 0.90 ± 0.05 in the residual CF{sub 2}HCl gas and K {sub enr}({sup 79}Br / {sup 81}Br) in the resultant Br{sub 2} product are obtained when the CF{sub 2}HCl : CF{sub 3}Br = 1 : 1 molecular mixture and CF{sub 3}Br molecules, respectively, are irradiated by the 9R(30) CO{sub 2} laser line (frequency, 1084.635 cm{sup −1}) at an energy density Φ ≈ 1.3 J cm{sup −2}. (laser isotope separation)

36 MATERIALS SCIENCE↗
DOE OSTI2022

Compositional texture engineering for highly stable wide-bandgap perovskite solar cells

The development of highly stable and efficient wide-bandgap (WBG) perovskite solar cells (PSCs) based on bromine-iodine (Br–I) mixed-halide perovskite (with Br greater than 20%) is critical to create tandem solar cells. However, issues with Br–I phase segregation under solar cell operational conditions (such as light and heat) limit the device voltage and operational stability. This challenge is often exacerbated by the ready defect formation associated with the rapid crystallization of Br-rich perovskite chemistry with antisolvent processes. We combined the rapid Br crystallization with a gentle gas-quench method to prepare highly textured columnar 1.75–electron volt Br–I mixed WBG perovskite films with reduced defect density. Here, with this approach, we obtained 1.75–electron volt WBG PSCs with greater than 20% power conversion efficiency, approximately 1.33-volt open-circuit voltage (V oc ), and excellent operational stability (less than 5% degradation over 1100 hours of operation under 1.2 sun at 65°C). When further integrated with 1.25–electron volt narrow-bandgap PSC, we obtained a 27.1% efficient, all-perovskite, two-terminal tandem device with a high V oc of 2.2 volts.

14 SOLAR ENERGY↗
DOE OSTI2021

Using MALDI-FTICR-MS Imaging to Track Low-Molecular-Weight Aromatic Derivatives of Fungal Decayed Wood

Low-molecular-weight (LMW) aromatics are crucial in meditating fungal processes for plant biomass decomposition. Some LMW compounds are employed as electron donors for oxidative degradation in brown rot (BR), an efficient wood-degrading strategy in fungi that selectively degrades carbohydrates but leaves modified lignins. Previous understandings of LMW aromatics were primarily based on “bulk extraction”, an approach that cannot fully reflect their real-time functions during BR. Here, we applied an optimized molecular imaging method that combines matrix-assisted laser desorption ionization (MALDI) with Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS) to directly measure the temporal profiles of BR aromatics as Rhodonia placenta decayed a wood wafer. We found that some phenolics were pre-existing in wood, while some (e.g., catechin-methyl ether and dihydroxy-dimethoxyflavan) were generated immediately after fungal activity. These pinpointed aromatics might be recruited to drive early BR oxidative mechanisms by generating Fenton reagents, Fe2+ and H2O2. As BR progressed, ligninolytic products were accumulated and then modified into various aromatic derivatives, confirming that R. placenta depolymerizes lignin. Together, this work confirms aromatic patterns that have been implicated in BR fungi, and it demonstrates the use of MALDI-FTICR-MS imaging as a new approach to monitor the temporal changes of LMW aromatics during wood degradation.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1977

Insulin and glucose responses during bed rest with isotonic and isometric exercise

The effects of daily intensive isotonic (68% maximum oxygen uptake) and isometric (21% maximum extension force) leg exercise on plasma insulin and glucose responses to an oral glucose tolerance test (OGTT) during 14-day bed-rest (BR) periods were investigated in seven young healthy men. The OGTT was given during ambulatory control and on day 10 of the no-exercise, isotonic, and isometric exercise BR periods during the 15-wk study. The subjects were placed on a controlled diet starting 10 days before each BR period. During BR, basal plasma glucose concentration remained unchanged with no exercise, but increased (P less 0.05) to 87-89 mg/100 ml with both exercise regimens on day 2, and then fell slightly below control levels on day 13. The fall in glucose content during BR was independent of the exercise regimen and was an adjustment for the loss of plasma volume. The intensity of the responses of insulin and glucose to the OGTT was inversely proportional to the total daily energy expenditure during BR. It was estimated that at least 1020 kcal/day must be provided by supplemental exercise to restore the hyperinsulinemia to control levels.

Dolkas, C. B.↗