固态 93Nb NMR 在催化中应用的理论和实验研究进展。

Theoretical and experimental insights into applicability of solid-state 93Nb NMR in catalysis.

机构信息

Boreskov Institute of Catalysis, 630090 Novosibirsk, Russia.

出版信息

Phys Chem Chem Phys. 2013 Apr 14;15(14):5115-31. doi: 10.1039/c3cp44016h.

Abstract

Ab initio DFT calculations of (93)Nb NMR parameters using the NMR-CASTEP code were performed for a series of over fifty individual niobates, and a good agreement has been found with experimental NMR parameters. New experimental and calculated (93)Nb NMR data were obtained for several compounds, AlNbO4, VNb9O25, K8Nb6O19 and Cs3NbO8, which are of particular interest for catalysis. Several interesting trends have been identified between (93)Nb NMR parameters and the specifics of niobium site environments in niobates. These trends may serve as useful guidelines in interpreting (93)Nb NMR spectra of complex niobium oxide systems, including amorphous samples and niobium-based multicomponent heterogeneous catalysts. Potential applications of (93)Nb NMR to study solid polyoxoniobates are discussed.

摘要

使用 NMR-CASTEP 代码对五十多种个别铌酸盐进行了（93）Nb NMR 参数的从头算 DFT 计算，与实验 NMR 参数吻合良好。获得了几种化合物（AlNbO4、VNb9O25、K8Nb6O19 和 Cs3NbO8）的新实验和计算（93）Nb NMR 数据，这些化合物对催化具有特殊意义。在（93）Nb NMR 参数与铌酸盐中铌原子环境的具体情况之间确定了几个有趣的趋势。这些趋势可能有助于解释复杂氧化铌系统（包括非晶样品和基于铌的多相异质催化剂）的（93）Nb NMR 谱。讨论了（93）Nb NMR 在研究固体多氧代铌酸盐方面的潜在应用。