93Nb NMR Chemical Shift Scale for Niobia Systems | Sciact - CRIS-система Института катализа

93Nb NMR Chemical Shift Scale for Niobia Systems Научная публикация

Журнал

Solid State Nuclear Magnetic Resonance
ISSN: 0926-2040 , E-ISSN: 1527-3326

Вых. Данные

Год: 2005, Том: 28, Номер: 2-4, Страницы: 204-224 Страниц : 21 DOI: 10.1016/j.ssnmr.2005.09.003

Ключевые слова

93Nb NMR, Chemical shift scale, High field MAS, Niobates, Solid-state NMR, STMAS

Авторы

Lapina Olga B. ¹ , Khabibulin Dzhalil F. ¹ , Romanenko Konstantin V. ¹ , Gan Zhehong ² , Zuev Mikhail G. ³ , Krasilnikov Vladimir N. ³ , Fedorov Vladimir E. ⁴

Организации

1	Boreskov Institute of Catalysis, SB RAS, Prosp. Lavrentieva 5, 630090 Novosibirsk, Russian Federation
2	NHMF Laboratory, Florida State University, CIMAR/NMR, Florida, USA
3	Institute of Solid State Chemistry, UB RAS, Ekaterinburg GSP-145, 620219 Russian Federation
4	Nikolaev Institute of Inorganic Chemistry, SB RAS, 630090 Novosibirsk, Russian Federation

Информация о финансировании (3)

1	Российский фонд фундаментальных исследований	04-03-33070
2	Сибирское отделение Российской академии наук	48
3	North Atlantic Treaty Organization	ESP.NR. NRCLG 981857

93Nb solid-state NMR spectra of a series of inorganic niobates with Nb in different oxygen coordination environments were measured. For all studied compounds the chemical shielding and quadrupole tensor parameters were determined using conventional and ultrahigh field NMR facilities, ultrahigh speed MAS, DQ STMAS, solid-echo and computer modeling. It has been demonstrated that the 93Nb isotropic chemical shift is sensitive to the coordination number of Nb sites. For the first time the 93Nb NMR chemical shift scale for NbOx polyhedra in solid materials has been proposed: for four-coordinated Nb sites, the isotropic shifts occur from −650 to −950 ppm; five-coordinated Nb sites have the isotropic shifts in the range of –900 to –980 ppm; for six-coordinated Nb sites the isotropic shifts vary from −900 to −1360 ppm; the shifts from −1200 to −1600 ppm are typical for seven-coordinated Nb sites; for eight-coordinated Nb sites the shifts are higher than −1400 ppm. The possible correlation between the value of the isotropic chemical shift and the ionic character of the NbOx–MOy polyhedra association has been suggested. The magnitude of the 93Nb quadrupole coupling constant depends on the local symmetry of Nb sites and may vary from hundreds of kHz to hundreds of MHz.

Lapina O.B. , Khabibulin D.F. , Romanenko K.V. , Gan Z. , Zuev M.G. , Krasilnikov V.N. , Fedorov V.E.
93Nb NMR Chemical Shift Scale for Niobia Systems
Solid State Nuclear Magnetic Resonance. 2005. V.28. N2-4. P.204-224. DOI: 10.1016/j.ssnmr.2005.09.003 WOS Scopus РИНЦ CAPlusCA PMID OpenAlex

Поступила в редакцию:	21 июн. 2005 г.
Опубликована в печати:	1 сент. 2005 г.
Опубликована online:	10 окт. 2005 г.

Web of science:	WOS:000234325100015
Scopus:	2-s2.0-29144433309
РИНЦ:	13478809
Chemical Abstracts:	2005:1320911
Chemical Abstracts (print):	145:179365
PMID (PubMed):	16216475
OpenAlex:	W2061230610

БД	Цитирований
Web of science	67
Scopus	67
РИНЦ	67
OpenAlex	76