Materials Data on Na2PrSiO5 by Materials Project

Na2PrSiO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.40–2.96 Å. Pr4+ is bonded to eight O2- atoms to form distorted PrO8 hexagonal bipyramids that share corners with two equivalent PrO8 hexagonal bipyramids, corners with four equivalent SiO4 tetrahedra, edges with two equivalent PrO8 hexagonal bipyramids, and an edgeedge with one SiO4 tetrahedra. There are a spread of Pr–O bond distances ranging from 2.43–2.59 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four equivalent PrO8 hexagonal bipyramids and an edgeedge with one PrO8 hexagonal bipyramid. There is one shorter (1.64 Å) and three longer (1.65 Å) Si–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Na1+, one Pr4+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Na1+, one Pr4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Na1+, two equivalent Pr4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Na1+ and two equivalent Pr4+ atoms.

Na₂PrSiO₅结晶于正交晶系Pnma空间群。该结构为三维框架结构。Na⁺采取八配位几何构型，与8个O²⁻原子成键，Na—O键的键长分布范围为2.40~2.96 Å。Pr⁴⁺与8个O²⁻原子配位，形成畸变的PrO₈六方双锥配位多面体；该配位多面体与2个等价的PrO₈六方双锥共享顶点、与4个等价的SiO₄四面体共享顶点，同时与2个等价的PrO₈六方双锥共享棱，并与1个SiO₄四面体共享一条棱。Pr—O键的键长分布范围为2.43~2.59 Å。Si⁴⁺与4个O²⁻原子配位，形成SiO₄四面体配位多面体；该四面体与4个等价的PrO₈六方双锥共享顶点，并与1个PrO₈六方双锥共享一条棱。Si—O键存在1条较短键长（1.64 Å）与3条较长键长（1.65 Å）。体系中存在4种不等价的O²⁻配位位点：在第一种O²⁻位点中，O²⁻采取1配位几何构型，与4个等价的Na⁺、1个Pr⁴⁺以及1个Si⁴⁺原子成键；在第二种O²⁻位点中，O²⁻采取1配位几何构型，与4个等价的Na⁺、1个Pr⁴⁺以及1个Si⁴⁺原子成键；在第三种O²⁻位点中，O²⁻采取1配位几何构型，与2个等价的Na⁺、2个等价的Pr⁴⁺以及1个Si⁴⁺原子成键；在第四种O²⁻位点中，O²⁻采取六配位几何构型，与4个等价的Na⁺以及2个等价的Pr⁴⁺原子成键。