Weidemann Martin L, Calaminus Robert, Menzel Nina, Johrendt Dirk
Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13(D), 81377, München, Germany.
Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, D-70569, Stuttgart.
Chemistry. 2024 Mar 7;30(14):e202303696. doi: 10.1002/chem.202303696. Epub 2024 Jan 17.
The quaternary phosphidosilicates AE Li SiP (AE=Ca, Sr, Eu) and Ba Li Si P were synthesized by heating the elements and Li P under argon atmosphere. Their crystal structures were determined by single crystal X-ray diffraction. AE Li SiP crystallize in a new layered structure type (P2 /m, Z=2) with CdI -analoguos layers. Edge sharing CaP octahedra are separated by layers of vertex-sharing SiP and LiP tetrahedra, which contain additional chains of LiP octahedra. Ba Li Si P forms likewise a new structure type (P2 /c, Z=16) with a three-dimensional network of SiP , Si P and LiP entities as well as one phosphorus site not bonded to silicon. Barium is located in capped trigonal prisms of phosphorus which form strongly corrugated layers. P and Si solid-state NMR spectra confirm the crystal structures of the compounds AE Li SiP . Li spectra show only one signal in spite of quite different crystallographic positions, which indicate possible Li mobility. However, this signal is much broader compared to the known Li conducting phosphidosilicates. Accordingly, electrochemical impedance measurements show low Li conductivities.
通过在氩气气氛下加热元素和Li₃P合成了四元磷硅化物AE LiSiP（AE = Ca、Sr、Eu）和BaLi₂SiP。通过单晶X射线衍射确定了它们的晶体结构。AE LiSiP以一种新的层状结构类型（P2 /m，Z = 2）结晶，具有CdI₂类层。边共享的CaP八面体被顶点共享的SiP和LiP四面体层隔开，其中包含额外的LiP八面体链。BaLi₂SiP同样形成一种新的结构类型（P2 /c，Z = 16），具有由SiP₄、Si₂P₆和LiP₄实体组成的三维网络以及一个未与硅键合的磷位点。钡位于磷的盖帽三角棱柱中，形成强烈起伏的层。³¹P和²⁹Si固态NMR光谱证实了化合物AE LiSiP的晶体结构。Li光谱尽管晶体学位置差异很大，但仅显示一个信号，这表明可能存在Li迁移率。然而，与已知的Li导电磷硅化物相比，该信号要宽得多。因此，电化学阻抗测量显示出低的Li电导率。
