Materials Data on KMgNbO15 by Materials Project
KMgNbO15 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. K is bonded in a 6-coordinate geometry to six O atoms. There are a spread of K–O bond distances ranging from 2.62–3.18 Å. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a distorted octahedral geometry to six O atoms. There are a spread of Mg–O bond distances ranging from 1.92–2.34 Å. In the second Mg site, Mg is bonded in an octahedral geometry to six O atoms. There are four shorter (2.00 Å) and two longer (2.31 Å) Mg–O bond lengths. Nb is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Nb–O bond distances ranging from 2.00–2.15 Å. There are fifteen inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one Nb and one O atom. The O–O bond length is 1.36 Å. In the second O site, O is bonded in a bent 120 degrees geometry to one Mg and one O atom. The O–O bond length is 1.24 Å. In the third O site, O is bonded in a 3-coordinate geometry to one K, one Nb, and one O atom. The O–O bond length is 1.46 Å. In the fourth O site, O is bonded in a single-bond geometry to one O atom. In the fifth O site, O is bonded in a distorted single-bond geometry to one Nb and one O atom. In the sixth O site, O is bonded in a 1-coordinate geometry to one Nb and one O atom. The O–O bond length is 1.43 Å. In the seventh O site, O is bonded in a 3-coordinate geometry to one Mg and one O atom. The O–O bond length is 1.29 Å. In the eighth O site, O is bonded in a 2-coordinate geometry to one Mg and one O atom. In the ninth O site, O is bonded in a 1-coordinate geometry to one K, one Nb, and one O atom. In the tenth O site, O is bonded in a 3-coordinate geometry to one K, one Mg, and one O atom. The O–O bond length is 1.38 Å. In the eleventh O site, O is bonded in a 2-coordinate geometry to one Nb and one O atom. The O–O bond length is 1.37 Å. In the twelfth O site, O is bonded in a bent 120 degrees geometry to one K and one Mg atom. In the thirteenth O site, O is bonded in a 3-coordinate geometry to one K, one Nb, and one O atom. In the fourteenth O site, O is bonded in a 3-coordinate geometry to one K, one Mg, and one O atom. In the fifteenth O site, O is bonded in a 2-coordinate geometry to one Nb and one O atom.