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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
S(O3I)2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two S(O3I)2 sheets oriented in the (0, 0, 1) direction. S2+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.49 Å) and two longer (1.51 Å) S–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one S2+ and one I5+ atom. The O–I bond length is 2.46 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one S2+ and one I5+ atom. The O–I bond length is 2.38 Å. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent I5+ atoms. There are one shorter (2.00 Å) and one longer (2.01 Å) O–I bond lengths. I5+ is bonded in a square co-planar geometry to four O2- atoms.
SrH(O3I)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Sr is bonded in a 9-coordinate geometry to one H and eight O atoms. The Sr–H bond length is 2.79 Å. There are a spread of Sr–O bond distances ranging from 2.57–3.16 Å. H is bonded in a single-bond geometry to one Sr atom. There are three inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to one Sr and one I atom. The O–I bond length is 1.82 Å. In the second O site, O is bonded in a bent 120 degrees geometry to one Sr and one I atom. The O–I bond length is 1.84 Å. In the third O site, O is bonded in a 1-coordinate geometry to two equivalent Sr and one I atom. The O–I bond length is 1.84 Å. I is bonded in a 3-coordinate geometry to three O atoms.
Pb3(SeO3)2I2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Pb+3.33+ sites. In the first Pb+3.33+ site, Pb+3.33+ is bonded in a 6-coordinate geometry to six O2- and two equivalent I1- atoms. There are a spread of Pb–O bond distances ranging from 2.61–2.84 Å. Both Pb–I bond lengths are 3.40 Å. In the second Pb+3.33+ site, Pb+3.33+ is bonded in a 5-coordinate geometry to five O2- and three equivalent I1- atoms. There are a spread of Pb–O bond distances ranging from 2.56–2.82 Å. There are a spread of Pb–I bond distances ranging from 3.28–3.59 Å. Se2+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.78 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two Pb+3.33+, one Se2+, and two equivalent I1- atoms. There are one shorter (3.42 Å) and one longer (3.77 Å) O–I bond lengths. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Pb+3.33+ and one Se2+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Pb+3.33+ and one Se2+ atom. I1- is bonded in a 6-coordinate geometry to four Pb+3.33+ and two equivalent O2- atoms.
K(O3I)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. K is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of K–O bond distances ranging from 2.77–3.22 Å. There are six inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees geometry to one K and one I atom. The O–I bond length is 1.84 Å. In the second O site, O is bonded in a 1-coordinate geometry to two equivalent K and one I atom. The O–I bond length is 1.83 Å. In the third O site, O is bonded in a distorted single-bond geometry to one K and one I atom. The O–I bond length is 1.84 Å. In the fourth O site, O is bonded in a trigonal non-coplanar geometry to two equivalent K and one I atom. The O–I bond length is 1.84 Å. In the fifth O site, O is bonded in a 1-coordinate geometry to two equivalent K and two I atoms. There are one shorter (1.83 Å) and one longer (2.72 Å) O–I bond lengths. In the sixth O site, O is bonded in a distorted bent 120 degrees geometry to one K and one I atom. The O–I bond length is 1.86 Å. There are two inequivalent I sites. In the first I site, I is bonded in a 3-coordinate geometry to four O atoms. In the second I site, I is bonded in a 3-coordinate geometry to three O atoms.
K(O3I)2 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.70–3.17 Å. In the second K site, K is bonded in a body-centered cubic geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.87–3.07 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one I atom. The O–I bond length is 1.81 Å. In the second O site, O is bonded in a 1-coordinate geometry to one K and two I atoms. There are one shorter (1.88 Å) and one longer (2.38 Å) O–I bond lengths. In the third O site, O is bonded in a 1-coordinate geometry to one K and one I atom. The O–I bond length is 1.83 Å. In the fourth O site, O is bonded in a 4-coordinate geometry to two equivalent K and two I atoms. There are one shorter (1.85 Å) and one longer (2.61 Å) O–I bond lengths. In the fifth O site, O is bonded in a 4-coordinate geometry to two K and two I atoms. There are one shorter (1.84 Å) and one longer (2.68 Å) O–I bond lengths. In the sixth O site, O is bonded in a 1-coordinate geometry to two equivalent K and one I atom. The O–I bond length is 1.83 Å. In the seventh O site, O is bonded in a distorted single-bond geometry to one K and one I atom. The O–I bond length is 1.91 Å. In the eighth O site, O is bonded in a 1-coordinate geometry to one K and one I atom. The O–I bond length is 1.89 Å. In the ninth O site, O is bonded in a 4-coordinate geometry to two K and two I atoms. There are one shorter (1.85 Å) and one longer (2.63 Å) O–I bond lengths. There are three inequivalent I sites. In the first I site, I is bonded in a 5-coordinate geometry to three O atoms. In the second I site, I is bonded in a 6-coordinate geometry to five O atoms. In the third I site, I is bonded in a 3-coordinate geometry to five O atoms.
K(O3I)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.75–2.91 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.66–3.05 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two equivalent K and one I atom. The O–I bond length is 1.83 Å. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one K and one I atom. The O–I bond length is 1.78 Å. In the third O site, O is bonded in a 1-coordinate geometry to two K and one I atom. The O–I bond length is 1.82 Å. In the fourth O site, O is bonded in a distorted trigonal planar geometry to one K and two I atoms. There are one shorter (1.97 Å) and one longer (2.14 Å) O–I bond lengths. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to one K and two I atoms. There are one shorter (1.91 Å) and one longer (2.27 Å) O–I bond lengths. In the sixth O site, O is bonded in a 1-coordinate geometry to two equivalent K and two I atoms. There are one shorter (1.82 Å) and one longer (2.75 Å) O–I bond lengths. In the seventh O site, O is bonded in a distorted trigonal non-coplanar geometry to two K and one I atom. The O–I bond length is 1.83 Å. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one K and one I atom. The O–I bond length is 1.82 Å. In the ninth O site, O is bonded in a bent 150 degrees geometry to one K and one I atom. The O–I bond length is 1.78 Å. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one K and two I atoms. There are one shorter (1.88 Å) and one longer (2.28 Å) O–I bond lengths. In the eleventh O site, O is bonded in a 1-coordinate geometry to one K and two I atoms. There are one shorter (1.87 Å) and one longer (2.37 Å) O–I bond lengths. In the twelfth O site, O is bonded in a 3-coordinate geometry to one K and two I atoms. There are one shorter (1.81 Å) and one longer (2.60 Å) O–I bond lengths. There are four inequivalent I sites. In the first I site, I is bonded in a distorted trigonal non-coplanar geometry to three O atoms. In the second I site, I is bonded in a distorted trigonal non-coplanar geometry to three O atoms. In the third I site, I is bonded in a distorted octahedral geometry to six O atoms. In the fourth I site, I is bonded in a 6-coordinate geometry to six O atoms.
The treatment of radioactive iodine released from nuclear power plants and radiological waste disposal sites is of great concern due to its high mobility and toxicity. In particular, iodide (I-) and iodate (IO3-) are the major iodine species of concern under various pHs and groundwater conditions. Herein, CoAl and NiAl layered double hydroxides (LDHs) were synthesized by a hydrothermal method and investigated to identify the removal mechanisms and efficiencies of both I- and IO3-. Both CoAl and NiAl LDHs exhibited rapid iodine removal processes within 20 min, following the pseudo-second-order model via ion-exchange with parent NO3- anion in the LDHs. The CoAl LDH’s maximum sorption capacities for I- and IO3- were about 1.67 and 2.16 mmol g-1, respectively, whereas for the NiAl LDH, these were about 2.10 and 2.26 mmol g-1, and they followed the Langmuir isotherm model. Interestingly, both the CoAl and NiAl LDHs showed a preferential ion-exchange affinity for IO3- over I-, which was attributed to the structural similarity of the IO3- and NO3- as well as new formation of secondary Co(or Ni)(IO3)2·2H2O phases. In addition, a desorption study indicated that the selectivity order was SO42- = IO3- = OH- > HCO3- > Cl- > NO3- = I- and demonstrated the higher retention of the IO3- than I- anion. This study provides insights into promising iodine sorbents and the different removal mechanisms of I- and IO3- using CoAl and NiAl LDHs.
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Ettringite is a naturally occurring mineral found in cementitious matrices that is known for its ability to incorporate environmentally mobile oxyanion contaminants. To better assess this immobilization mechanism for contaminants within cementitious waste forms intended for nuclear waste storage, this work explores how mixed oxyanion contaminants compete for ettringite incorporation and influence the evolving mineralogy. Ettringite was precipitated in the presence of TcO4-, IO3-, and/or CrO42-, known contaminants of concern to nuclear waste treatment, over pre-determined precipitation periods. Solution analyses quantified contaminant removal and the collected solid was characterized using bulk and microprobe XRD coupled with PDF and microprobe XRF analyses. Results suggest that =96% IO3- is removed from solution, regardless of ettringite precipitation time or the presence of TcO4- or CrO42-. However, TcO4- removal remained <20%, was not significantly improved with longer ettringite precipitation times, and significantly decreased in the presence of IO3-. When IO3- is comingled with CrO42, gypsum is formed as a secondary mineral phase, which results in oxyanion partitioning among mineral phases, e.g., IO3- incorporation into ettringite and CrO42- incorporation into gypsum via SO42- substitution. Results from this work exemplify the importance of competitive immobilization when assessing waste form performance and environmental risk of contaminant release.
Bi(IO3)3 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Bi(IO3)3 sheet oriented in the (-1, 0, 2) direction. Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.41–2.73 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Bi3+ and one I5+ atom. The O–I bond length is 1.83 Å. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Bi3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Bi3+ and one I5+ atom. The O–I bond length is 1.86 Å. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Bi3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Bi3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one I5+ atom. The O–I bond length is 1.86 Å. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.83 Å. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Bi3+ and one I5+ atom. The O–I bond length is 1.86 Å. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Bi3+ and one I5+ atom. The O–I bond length is 1.86 Å. There are three inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the second I5+ site, I5+ is bonded in a 6-coordinate geometry to three O2- atoms. In the third I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms.
Er(IO3)3 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Er(IO3)3 sheet oriented in the (-1, 0, 2) direction. Er3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Er–O bond distances ranging from 2.28–2.41 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Er3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Er3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.86 Å. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Er3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Er3+ and one I5+ atom. The O–I bond length is 1.86 Å. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.84 Å. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Er3+ and one I5+ atom. The O–I bond length is 1.82 Å. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to one Er3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Er3+ and one I5+ atom. The O–I bond length is 1.84 Å. There are three inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 5-coordinate geometry to three O2- atoms. In the second I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the third I5+ site, I5+ is bonded in a 6-coordinate geometry to three O2- atoms.
Lu(IO3)3 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Lu(IO3)3 sheet oriented in the (-1, 0, 2) direction. Lu3+ is bonded in a distorted pentagonal bipyramidal geometry to seven O2- atoms. There are a spread of Lu–O bond distances ranging from 2.22–2.36 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Lu3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.86 Å. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Lu3+ and one I5+ atom. The O–I bond length is 1.86 Å. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Lu3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Lu3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.84 Å. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Lu3+ and one I5+ atom. The O–I bond length is 1.81 Å. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to one Lu3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Lu3+ and one I5+ atom. The O–I bond length is 1.84 Å. There are three inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 6-coordinate geometry to three O2- atoms. In the second I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the third I5+ site, I5+ is bonded in a 5-coordinate geometry to three O2- atoms.
Dy(O3I)3 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Dy(O3I)3 sheet oriented in the (-1, 0, 2) direction. Dy3+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of Dy–O bond distances ranging from 2.30–2.83 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Dy3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Dy3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Dy3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Dy3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one I5+ atom. The O–I bond length is 1.87 Å. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Dy3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Dy3+ and one I5+ atom. The O–I bond length is 1.86 Å. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.84 Å. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to one Dy3+ and one I5+ atom. The O–I bond length is 1.82 Å. There are three inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 5-coordinate geometry to three O2- atoms. In the second I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the third I5+ site, I5+ is bonded in a 6-coordinate geometry to three O2- atoms.
Y(O3I)3 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Y(O3I)3 sheet oriented in the (-1, 0, 2) direction. Y3+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.31–2.86 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Y3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.84 Å. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Y3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Y3+ and one I5+ atom. The O–I bond length is 1.82 Å. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one I5+ atom. The O–I bond length is 1.86 Å. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Y3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Y3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Y3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Y3+ and one I5+ atom. The O–I bond length is 1.84 Å. There are three inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the second I5+ site, I5+ is bonded in a 6-coordinate geometry to three O2- atoms. In the third I5+ site, I5+ is bonded in a 5-coordinate geometry to three O2- atoms.
IO3 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. there are three inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to two equivalent I atoms. There are one shorter (1.85 Å) and one longer (2.40 Å) O–I bond lengths. In the second O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent I atoms. There are one shorter (1.87 Å) and one longer (2.20 Å) O–I bond lengths. In the third O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent I atoms. There are one shorter (1.89 Å) and one longer (2.20 Å) O–I bond lengths. I is bonded to six O atoms to form distorted corner-sharing IO6 octahedra. The corner-sharing octahedra tilt angles range from 45–47°.
Ho(O3I)3 crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. Ho3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ho–O bond distances ranging from 2.19–2.74 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Ho3+ and two I5+ atoms. There are one shorter (1.93 Å) and one longer (2.45 Å) O–I bond lengths. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Ho3+ and two equivalent I5+ atoms. Both O–I bond lengths are 2.80 Å. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ho3+ and two equivalent I5+ atoms. Both O–I bond lengths are 2.12 Å. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Ho3+ and one I5+ atom. The O–I bond length is 1.90 Å. There are two inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 6-coordinate geometry to six O2- atoms. In the second I5+ site, I5+ is bonded in a 4-coordinate geometry to four equivalent O2- atoms.
TiAg2(O3I)6 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Ti4+ is bonded in an octahedral geometry to six equivalent O2- atoms. All Ti–O bond lengths are 1.97 Å. Ag1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ag–O bond distances ranging from 2.58–2.99 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Ag1+ and one I5+ atom. The O–I bond length is 1.84 Å. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Ag1+ and one I5+ atom. The O–I bond length is 1.84 Å. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Ti4+, one Ag1+, and one I5+ atom. The O–I bond length is 1.91 Å. I5+ is bonded in a 4-coordinate geometry to three O2- atoms.