Materials Data on Eu(GaSe2)2 by Materials Project
EuGa2Se4 crystallizes in the orthorhombic Cccm space group. The structure is three-dimensional. Eu2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are four shorter (3.26 Å) and four longer (3.29 Å) Eu–Se bond lengths. Ga3+ is bonded to four Se2- atoms to form edge-sharing GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.45–2.48 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent Eu2+ and two equivalent Ga3+ atoms. In the second Se2- site, Se2- is bonded to two equivalent Eu2+ and two equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing SeEu2Ga2 trigonal pyramids.