Materials Data on Na4Eu2SiP4 by Materials Project

Abstract

Na4Eu2SiP4 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to one Si4- and five P1- atoms. The Na–Si bond length is 3.22 Å. There are a spread of Na–P bond distances ranging from 3.03–3.25 Å. In the second Na1+ site, Na1+ is bonded in a 4-coordinate geometry to four P1- atoms. There are a spread of Na–P bond distances ranging from 2.88–3.14 Å. In the third Na1+ site, Na1+ is bonded to four P1- atoms to form distorted NaP4 trigonal pyramids that share corners with two equivalent SiNaEuP4 tetrahedra, corners with six NaP4 trigonal pyramids, and an edgeedge with one SiNaEuP4 tetrahedra. There are a spread of Na–P bond distances ranging from 2.85–3.07 Å. In the fourth Na1+ site, Na1+ is bonded to four P1- atoms to form distorted NaP4 trigonal pyramids that share corners with two equivalent SiNaEuP4 tetrahedra, corners with four equivalent NaP4 trigonal pyramids, and an edgeedge with one SiNaEuP4 tetrahedra. There are a spread of Na–P bond distances ranging from 2.93–3.16 Å. There are two inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded in a 5-coordinate geometry to five P1- atoms. There are a spread of Eu–P bond distances ranging from 2.99–3.14 Å. In the second Eu2+ site, Eu2+ is bonded in a 7-coordinate geometry to one Si4- and six P1- atoms. The Eu–Si bond length is 3.22 Å. There are a spread of Eu–P bond distances ranging from 2.98–3.36 Å. Si4- is bonded to one Na1+, one Eu2+, and four P1- atoms to form distorted SiNaEuP4 tetrahedra that share corners with four NaP4 trigonal pyramids and edges with two NaP4 trigonal pyramids. There are a spread of Si–P bond distances ranging from 2.28–2.34 Å. There are four inequivalent P1- sites. In the first P1- site, P1- is bonded in a 7-coordinate geometry to four Na1+, three Eu2+, and one Si4- atom. In the second P1- site, P1- is bonded in a 8-coordinate geometry to four Na1+, three Eu2+, and one Si4- atom. In the third P1- site, P1- is bonded in a 8-coordinate geometry to four Na1+, three Eu2+, and one Si4- atom. In the fourth P1- site, P1- is bonded in a 8-coordinate geometry to five Na1+, two equivalent Eu2+, and one Si4- atom.