DOI: 10.17188/1273999
title: Materials Data on Ba21Al40 by Materials Project

description: Ba21Al40 crystallizes in the trigonal P31m space group. The structure is three-dimensional. there are nine inequivalent Ba sites. In the first Ba site, Ba is bonded in a 12-coordinate geometry to four Ba and twelve Al atoms. There are one shorter (3.72 Å) and three longer (3.75 Å) Ba–Ba bond lengths. There are a spread of Ba–Al bond distances ranging from 3.50–3.73 Å. In the second Ba site, Ba is bonded in a 12-coordinate geometry to three equivalent Ba and twelve Al atoms. There are a spread of Ba–Al bond distances ranging from 3.56–3.63 Å. In the third Ba site, Ba is bonded in a 12-coordinate geometry to three equivalent Ba and twelve Al atoms. There are two shorter (3.69 Å) and one longer (3.90 Å) Ba–Ba bond lengths. There are a spread of Ba–Al bond distances ranging from 3.50–3.63 Å. In the fourth Ba site, Ba is bonded in a 1-coordinate geometry to one Ba and ten Al atoms. The Ba–Ba bond length is 3.74 Å. There are a spread of Ba–Al bond distances ranging from 3.55–3.60 Å. In the fifth Ba site, Ba is bonded in a 8-coordinate geometry to four Ba and thirteen Al atoms. There are a spread of Ba–Al bond distances ranging from 3.52–3.81 Å. In the sixth Ba site, Ba is bonded in a 7-coordinate geometry to nine Al atoms. There are a spread of Ba–Al bond distances ranging from 3.86–3.99 Å. In the seventh Ba site, Ba is bonded in a 1-coordinate geometry to ten Al atoms. There are a spread of Ba–Al bond distances ranging from 3.51–3.58 Å. In the eighth Ba site, Ba is bonded in a 1-coordinate geometry to ten Al atoms. There are a spread of Ba–Al bond distances ranging from 3.53–3.62 Å. In the ninth Ba site, Ba is bonded in a 3-coordinate geometry to four Ba and thirteen Al atoms. There are a spread of Ba–Al bond distances ranging from 3.52–3.72 Å. There are thirteen inequivalent Al sites. In the first Al site, Al is bonded in a distorted q6 geometry to six Ba and four Al atoms. There are a spread of Al–Al bond distances ranging from 2.66–2.95 Å. In the second Al site, Al is bonded in a 10-coordinate geometry to six Ba and four Al atoms. There are a spread of Al–Al bond distances ranging from 2.73–2.87 Å. In the third Al site, Al is bonded in a 9-coordinate geometry to five Ba and four Al atoms. There are a spread of Al–Al bond distances ranging from 2.72–3.01 Å. In the fourth Al site, Al is bonded in a 9-coordinate geometry to five Ba and four Al atoms. There are one shorter (2.72 Å) and one longer (2.80 Å) Al–Al bond lengths. In the fifth Al site, Al is bonded in a body-centered cubic geometry to four Ba and four Al atoms. There are three shorter (2.73 Å) and one longer (2.75 Å) Al–Al bond lengths. In the sixth Al site, Al is bonded in a 10-coordinate geometry to seven Ba and three equivalent Al atoms. In the seventh Al site, Al is bonded in a distorted q6 geometry to six Ba and four Al atoms. There are one shorter (2.72 Å) and one longer (2.77 Å) Al–Al bond lengths. In the eighth Al site, Al is bonded in a distorted q6 geometry to six Ba and four Al atoms. The Al–Al bond length is 2.75 Å. In the ninth Al site, Al is bonded in a 10-coordinate geometry to six Ba and four Al atoms. In the tenth Al site, Al is bonded in a 10-coordinate geometry to seven Ba and three Al atoms. In the eleventh Al site, Al is bonded to six Ba and six Al atoms to form edge-sharing AlBa6Al6 cuboctahedra. In the twelfth Al site, Al is bonded in a 10-coordinate geometry to seven Ba and three equivalent Al atoms. In the thirteenth Al site, Al is bonded in a 10-coordinate geometry to six Ba and four Al atoms.