Solid-state NMR studies of the inorganic materials

Abstract

Inorganic materials such as PbMnCl3, KHSO4, NaSmP2S6, AgNb2PS10, and Au0.5Nb2PS10 are studied by using a solid-state NMR spectroscopy. In chapter Ⅱ, the structural phase transition of ferroelastic RbMnCl3 is observed by using a solid-state 87Rb NMR spectroscopy. The 87Rb NMR quadrupole coupling constants and asymmetry parameters as a function of temperature in powder and single crystal are determined to detect the phase transition. Changes in the relative peak intensity between Rb(Ⅰ) and Rb(Ⅱ) sites seen to suggest the existence of anomalous intermediate phase confirmed by the DSC and XRD studies. In chapter Ⅲ, the first phase transition of KHSO4 is confimed by the measurement of 39K NMR quadrupole coupling constants and the asymmetry parameters for two K sites, K(Ⅰ) and K(Ⅱ), at room temperature are measured by using 39K dingle crystal NMR. The isotropic chemical shift and chemical shift anisotropy of two distinct hydrogen atoms are determined by using 1H MAS NMR to relate with x-ray crystallographic data. In chapter Ⅳ, 31P NMR chemical shielding parameters of NaSmP2S6, AgNb2PS10, and Au0.5Nb2PS10 are determined by using solid-state 31P static and MAS NMR to get the relationship with x-ray crystallographic structure data. And 93Nb NMR quadrupole coupling constants and asymmetry parameters of AgNb2PS10 and Au0.5Nb2PS10 are obtained.;Solid-state NMR spectroscopy를 사용하여 PbMnCl3, KHSO4, NaSmP2S6, AgNb2PS10, Au0.5Nb2PS10과 같은 무기 물질들을 연구하였다. 2장에서는 PbMnCl3의 structural phase transition을 87Rb NMR spectroscopy를 이용하여 관찰하였다. Phase Transition을 측정하기 위해 87Rb NMR quadrupole coupling constant와 asymmetry parameter를 구하였다. Rb(Ⅰ)과 Rb(Ⅱ) 사이의 상대적 peak 세기의 변화로서 anomalous intermediate phase가 있는 것처럼 보여졌고 DSC와 XRD로서 확인할 수 있었다. 3장에서는 39K NMR spin-littice(T1) relaxation time을 측정하여 KHSO4의 첫 번째 Phase transition을 확인할 수 있었고 K(Ⅰ)과 K(Ⅱ) site의 39K single crystal NMR을 이용하여 구하였다. 1H MAS NMR을 이용하여 chemical hielding parameter를 구하여 x-ray crysallographic data와 관련하여 분석하였다. 4장에서는 NaSmP2S6, AgNb2PS10, Au0.5Nb2PS10의 31P NMR을 이용하여 chemical shielding parameter를 구했고 x-ray crystallographic data 와의 관련성을 알아보았다. AgNb2PS10, Au0.5Nb2PS10의 93Nb NMR quadrupole coupling constant 와 asymmetry parameter을 구하였다.