Materials Data on BaCa3 by Materials Project

Abstract

BaCa3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ba is bonded to twelve Ca atoms to form BaCa12 cuboctahedra that share corners with six equivalent BaCa12 cuboctahedra, corners with twelve CaBa4Ca8 cuboctahedra, edges with eighteen CaBa4Ca8 cuboctahedra, faces with eight equivalent BaCa12 cuboctahedra, and faces with twelve CaBa4Ca8 cuboctahedra. There are six shorter (4.04 Å) and six longer (4.08 Å) Ba–Ca bond lengths. There are three inequivalent Ca sites. In the first Ca site, Ca is bonded to four equivalent Ba and eight Ca atoms to form CaBa4Ca8 cuboctahedra that share corners with four equivalent BaCa12 cuboctahedra, corners with fourteen equivalent CaBa4Ca8 cuboctahedra, edges with six equivalent BaCa12 cuboctahedra, edges with twelve CaBa4Ca8 cuboctahedra, faces with four equivalent BaCa12 cuboctahedra, and faces with sixteen CaBa4Ca8 cuboctahedra. There are a spread of Ca–Ca bond distances ranging from 3.98–4.11 Å. In the second Ca site, Ca is bonded to four equivalent Ba and eight Ca atoms to form CaBa4Ca8 cuboctahedra that share corners with four equivalent BaCa12 cuboctahedra, corners with fourteen CaBa4Ca8 cuboctahedra, edges with six equivalent BaCa12 cuboctahedra, edges with twelve CaBa4Ca8 cuboctahedra, faces with four equivalent BaCa12 cuboctahedra, and faces with sixteen CaBa4Ca8 cuboctahedra. There are a spread of Ca–Ca bond distances ranging from 3.98–4.11 Å. In the third Ca site, Ca is bonded to four equivalent Ba and eight Ca atoms to form CaBa4Ca8 cuboctahedra that share corners with four equivalent BaCa12 cuboctahedra, corners with fourteen CaBa4Ca8 cuboctahedra, edges with six equivalent BaCa12 cuboctahedra, edges with twelve CaBa4Ca8 cuboctahedra, faces with four equivalent BaCa12 cuboctahedra, and faces with sixteen CaBa4Ca8 cuboctahedra.