Hydrogen bonds in Na2S·5H2O: X-ray diffraction and vibrational spectroscopic study

Abstract

The crystal structure (at 295 K) and Raman spectra (at 295 and 75 K) of Na₂S·5H₂O have been studied paying attention to the hydrogen bonds. Crystals are orthorhombic, space group Cmcm, with a= 6.476(1), b= 12.536(2), c= 8.686(1)Å, and Z= 4; R= 0.024 for 474 independent reflections collected using Mo-K_α radiation. The structure contains three different kinds of O–H ⋯ S bonds with O ⋯ S = 3.30, 3.32, and 3.45 Å, and with H ⋯ S = 2.35, 2.36, and 2.53 Å. At 75 K the uncoupled O–D frequencies of the isotopically dilute HOD molecules are 2 379, 2 398, and 2 473 cm^–1.