DOE OSTI2020
Sr19In8N7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are twelve inequivalent Sr sites. In the first Sr site, Sr is bonded in a linear geometry to four In and two N atoms. There are one shorter (3.97 Å) and three longer (3.98 Å) Sr–In bond lengths. There are one shorter (2.51 Å) and one longer (2.63 Å) Sr–N bond lengths. In the second Sr site, Sr is bonded in an L-shaped geometry to four In and two N atoms. All Sr–In bond lengths are 3.75 Å. Both Sr–N bond lengths are 2.60 Å. In the third Sr site, Sr is bonded in an L-shaped geometry to four In and two N atoms. All Sr–In bond lengths are 3.75 Å. Both Sr–N bond lengths are 2.60 Å. In the fourth Sr site, Sr is bonded in a linear geometry to four In and two N atoms. There are one shorter (3.97 Å) and three longer (3.98 Å) Sr–In bond lengths. There are one shorter (2.51 Å) and one longer (2.63 Å) Sr–N bond lengths. In the fifth Sr site, Sr is bonded in an L-shaped geometry to four In and two N atoms. All Sr–In bond lengths are 3.75 Å. Both Sr–N bond lengths are 2.60 Å. In the sixth Sr site, Sr is bonded in a linear geometry to four In and two N atoms. There are one shorter (3.97 Å) and three longer (3.98 Å) Sr–In bond lengths. There are one shorter (2.51 Å) and one longer (2.63 Å) Sr–N bond lengths. In the seventh Sr site, Sr is bonded in an L-shaped geometry to four In and two N atoms. All Sr–In bond lengths are 3.75 Å. Both Sr–N bond lengths are 2.60 Å. In the eighth Sr site, Sr is bonded in an L-shaped geometry to four In and two N atoms. All Sr–In bond lengths are 3.75 Å. Both Sr–N bond lengths are 2.60 Å. In the ninth Sr site, Sr is bonded in an octahedral geometry to six N atoms. All Sr–N bond lengths are 2.74 Å. In the tenth Sr site, Sr is bonded in a linear geometry to four In and two N atoms. All Sr–In bond lengths are 3.98 Å. There are one shorter (2.51 Å) and one longer (2.63 Å) Sr–N bond lengths. In the eleventh Sr site, Sr is bonded in an L-shaped geometry to four In and two equivalent N atoms. All Sr–In bond lengths are 3.75 Å. Both Sr–N bond lengths are 2.60 Å. In the twelfth Sr site, Sr is bonded in an L-shaped geometry to four In and two equivalent N atoms. All Sr–In bond lengths are 3.75 Å. Both Sr–N bond lengths are 2.60 Å. There are six inequivalent In sites. In the first In site, In is bonded to nine Sr and three In atoms to form InSr9In3 cuboctahedra that share corners with three InSr9In3 cuboctahedra, corners with six NSr6 octahedra, edges with three equivalent InSr9In3 cuboctahedra, faces with six InSr9In3 cuboctahedra, and faces with four NSr6 octahedra. The corner-sharing octahedral tilt angles are 49°. All In–In bond lengths are 3.20 Å. In the second In site, In is bonded to nine Sr and three In atoms to form InSr9In3 cuboctahedra that share corners with three InSr9In3 cuboctahedra, corners with six NSr6 octahedra, edges with three equivalent InSr9In3 cuboctahedra, faces with six InSr9In3 cuboctahedra, and faces with four NSr6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are two shorter (3.20 Å) and one longer (3.21 Å) In–In bond lengths. In the third In site, In is bonded to nine Sr and three In atoms to form InSr9In3 cuboctahedra that share corners with three InSr9In3 cuboctahedra, corners with six NSr6 octahedra, edges with three equivalent InSr9In3 cuboctahedra, faces with six InSr9In3 cuboctahedra, and faces with four NSr6 octahedra. The corner-sharing octahedral tilt angles are 49°. Both In–In bond lengths are 3.20 Å. In the fourth In site, In is bonded to nine Sr and three In atoms to form InSr9In3 cuboctahedra that share corners with three InSr9In3 cuboctahedra, corners with six NSr6 octahedra, edges with three equivalent InSr9In3 cuboctahedra, faces with six InSr9In3 cuboctahedra, and faces with four NSr6 octahedra. The corner-sharing octahedral tilt angles are 49°. Both In–In bond lengths are 3.20 Å. In the fifth In site, In is bonded to nine Sr and three In atoms to form InSr9In3 cuboctahedra that share corners with three InSr9In3 cuboctahedra, corners with six NSr6 octahedra, edges with three equivalent InSr9In3 cuboctahedra, faces with six InSr9In3 cuboctahedra, and faces with four NSr6 octahedra. The corner-sharing octahedral tilt angles are 49°. The In–In bond length is 3.20 Å. In the sixth In site, In is bonded to nine Sr and three In atoms to form InSr9In3 cuboctahedra that share corners with three InSr9In3 cuboctahedra, corners with six NSr6 octahedra, edges with three equivalent InSr9In3 cuboctahedra, faces with six InSr9In3 cuboctahedra, and faces with four NSr6 octahedra. The corner-sharing octahedral tilt angles are 49°. The In–In bond length is 3.20 Å. There are five inequivalent N sites. In the first N site, N is bonded to six Sr atoms to form NSr6 octahedra that share corners with eight InSr9In3 cuboctahedra, corners with two NSr6 octahedra, edges with four NSr6 octahedra, and faces with four InSr9In3 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. In the second N site, N is bonded to six Sr atoms to form NSr6 octahedra that share corners with eight InSr9In3 cuboctahedra, corners with two NSr6 octahedra, edges with four NSr6 octahedra, and faces with four InSr9In3 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. In the third N site, N is bonded to six Sr atoms to form NSr6 octahedra that share corners with eight InSr9In3 cuboctahedra, corners with two NSr6 octahedra, edges with four NSr6 octahedra, and faces with four InSr9In3 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth N site, N is bonded to six Sr atoms to form NSr6 octahedra that share corners with eight InSr9In3 cuboctahedra, corners with two NSr6 octahedra, edges with four NSr6 octahedra, and faces with four InSr9In3 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth N site, N is bonded to six Sr atoms to form NSr6 octahedra that share corners with six NSr6 octahedra and faces with eight InSr9In3 cuboctahedra. The corner-sharing octahedral tilt angles are 0°.