Zaikina Julia V, Kovnir Kirill A, Haarmann Frank, Schnelle Walter, Burkhardt Ulrich, Borrmann Horst, Schwarz Ulrich, Grin Yuri, Shevelkov Andrei V
Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Strabe 40, 01187 Dresden, Germany.
Chemistry. 2008;14(18):5414-22. doi: 10.1002/chem.200800453.
A new representative of a very rare clathrate III family, Si130P42Te21, has been synthesized from the elements. It crystallizes in the tetragonal space group P4(2)/mnm (no. 136) with the unit cell parameters a=19.2632(3) angstroms, c=10.0706(2) angstroms. Single crystal X-ray diffraction and solid state 31P NMR revealed a non-random distribution of phosphorus atoms over the framework positions. The crystal structure features a peculiar packing of large polyhedra Te@(Si/P)(n) never observed before for cationic clathrates. Despite the structural complexity, the composition of the novel clathrate Is in accordance with the Zintl rule, which was confirmed by a combination of optical metallography, scanning electron microscopy (SEM) and wavelength dispersive X-ray spectroscopy (WDXS), as well as by diamagnetic and semiconducting behavior of the synthesized phase. Clathrate Si130P42Te21 exhibits the highest reported thermal stability for this class of materials, it decomposes at 1510 K. This opens new perspectives for the creation of clathrate-based materials for high-temperature applications.
一种非常罕见的笼形包合物III族的新代表物Si130P42Te21已由元素合成。它结晶于四方空间群P4(2)/mnm（编号136），晶胞参数a = 19.2632(3)埃，c = 10.0706(2)埃。单晶X射线衍射和固态31P核磁共振表明磷原子在骨架位置上呈非随机分布。晶体结构的特征是大的多面体Te@(Si/P)(n)有独特的堆积方式，这在阳离子笼形包合物中从未见过。尽管结构复杂，但这种新型笼形包合物的组成符合津特耳规则，这通过光学金相学、扫描电子显微镜（SEM）和波长色散X射线光谱（WDXS）的组合，以及合成相的抗磁性和半导体行为得到了证实。笼形包合物Si130P42Te21表现出此类材料中报道的最高热稳定性，它在1510 K分解。这为高温应用的笼形包合物基材料的创制开辟了新的前景。
