• Nadezhda V. Shchipalkina
  • Natalia N. Zubkova
  • Alexey R. Kotelnikov
  • Natalia N. Koshlyakova
  • Igor V. Pekov
  • Dmitry A. Ksenofontov
  • Sergey N. Britvin

The synthetic nosean- and haüyne-like aluminosilicates with (MoO4)2− and (WO4)2− extra-framework anions were synthesized in H2O-bearing systems (3 kbar, 750 °C) and studied by means of electron microprobe analysis, Raman spectroscopy, powder and single-crystal X-ray diffraction. The nosean-like phase contains up to 10.6 wt% MoO3 and up to 5.1 wt% WO3; the maximum content of MoO3 in the haüyne-like phase is 22.5 wt%. The nosean-like phase with (MoO4)2− and (WO4)2− is cubic, P-43m, a = 9.1278(10) Å, V = 760.498(14) Å3, Z = 1. This compound with the crystal chemical formula Na7.68[(Al,Si)12O24] {[(Mo0.65W0.35)O4]0.780.22}·H2O has a disordered Al/Si framework, that is caused by the high temperature of crystallization (t = 750 °C) with further quenching at room temperature. Despite the same conditions of synthesis, the haüyne-like phase with (MoO4)2−, Na5.12Ca1.92[Al6Si6O24](MoO4)1.52 has an Al/Si-ordered framework. Its space group is P-43n, a = 9.1516(4) Å, V = 766.46(6) Å3, Z = 1. In both synthesized sodalite-type aluminosilicates the anion groups (MoO4)2− and (WO4)2− are dynamically disordered. The polarized Raman spectra of both aluminosilicates show that Raman-active modes of (MoO4)2− and (WO4)2− correspond to vibrations of tetrahedral anions with symmetry Td. The presence of H2O was fixed only in the nosean-like compound and no preferred orientation of water molecule was detected.

Original languageEnglish
Article number19
Number of pages11
JournalPhysics and Chemistry of Minerals
Volume48
Issue number5
DOIs
StatePublished - May 2021

    Scopus subject areas

  • Geochemistry and Petrology
  • Materials Science(all)

    Research areas

  • Aluminosilicates, Crystal chemistry, Haüyne, Raman spectroscopy, Sodalite, Synthesis, yne, Ha&#252

ID: 76725287