DOE OSTI2020
ReNCl4 crystallizes in the monoclinic P2_1/m space group. The structure is two-dimensional and consists of one ReNCl4 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Re7+ sites. In the first Re7+ site, Re7+ is bonded to five Cl1- atoms to form corner-sharing ReCl5 square pyramids. There are a spread of Re–Cl bond distances ranging from 2.28–2.42 Å. In the second Re7+ site, Re7+ is bonded in a rectangular see-saw-like geometry to four Cl1- atoms. There are two shorter (2.24 Å) and two longer (2.40 Å) Re–Cl bond lengths. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a 7-coordinate geometry to seven Cl1- atoms. There are a spread of N–Cl bond distances ranging from 3.14–3.65 Å. In the second N3- site, N3- is bonded in a single-bond geometry to one Cl1- atom. The N–Cl bond length is 1.61 Å. There are eight inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Re7+ atoms. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ and one N3- atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ and two equivalent N3- atoms. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ and two equivalent N3- atoms. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ atom. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ and two equivalent N3- atoms. In the seventh Cl1- site, Cl1- is bonded in a single-bond geometry to three N3- atoms. In the eighth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two equivalent Re7+ atoms.