نتایج جستجو برای: nmr shielding

تعداد نتایج: 67435  

Journal: :Physical chemistry chemical physics : PCCP 2011
Jérôme Cuny Kateryna Sykina Bruno Fontaine Laurent Le Pollès Chris J Pickard Régis Gautier

Solid-state (95)Mo nuclear magnetic resonance (NMR) properties of molybdenum hexacarbonyl have been computed using density functional theory (DFT) based methods. Both quadrupolar coupling and chemical shift parameters were evaluated and compared with parameters of high precision determined using single-crystal (95)Mo NMR experiments. Within a molecular approach, the effects of major computation...

Journal: :The journal of physical chemistry. A 2008
Gang Wu Victor Terskikh

We report a multinuclear solid-state ( (23)Na, (39)K, (87)Rb, (133)Cs) NMR study of tetraphenylborate salts, M[BPh 4] (M = Na, K, Rb, Cs). These compounds are isostructural in the solid state with the alkali metal ion surrounded by four phenyl groups resulting in strong cation-pi interactions. From analyses of solid-state NMR spectra obtained under stationary and magic-angle spinning (MAS) cond...

Journal: :Journal of chemical theory and computation 2016
Peter B Karadakov Kate E Horner

Differences in nuclear isotropic magnetic shieldings give rise to the chemical shifts measured in NMR experiments. In contrast to existing NMR experimental techniques, quantum chemical methods are capable of calculating isotropic magnetic shieldings not just at nuclei, but also at any point in the space surrounding a molecule. Using s-trans-1,3-butadiene, ethane, ethene, and ethyne as examples,...

2011
Jérôme Cuny Kateryna Sykina Bruno Fontaine Laurent Le Pollès Chris J. Pickard Régis Gautier

Solid-state Mo nuclear magnetic resonance (NMR) properties of molybdenum hexacarbonyl have been computed using density functional theory (DFT) based methods. Both quadrupolar coupling and chemical shift parameters were evaluated and compared with parameters of high precision determined using single-crystal Mo NMR experiments. Within a molecular approach, the effects of major computational param...

2013
Peter Kroneck Horst Oehler

Tetrahedrally coordinated copper(I) complexes C11L4X have been synthesized, L being P(OR)3, PR3 or P(R)n(OR)3-n, and X being a non-coordinating anion such as Perchlorate or tetrafluoroborate. Depending on the nature of the bound phosphorus ligand the Cu(I) complexes give well resolved 63Cu NMR spectra including a quintet signal due to spin-spin coupling between 63Cu and 31P. The 63Cu NMR spectr...

Journal: :Physical chemistry chemical physics : PCCP 2009
Peter J Pallister Igor L Moudrakovski John A Ripmeester

Due to sensitivity problems, (25)Mg remains a largely under-explored nucleus in solid state NMR spectroscopy. In this work at an ultrahigh magnetic field of 21.1 T, we have studied at natural abundance the (25)Mg solid state (SS) NMR spectra for a number of previously unreported magnesium compounds with known crystal structures. Some previously reported compounds have been revisited to clarify ...

Journal: :Dalton transactions 2008
I del Rosal L Maron R Poteau F Jolibois

Transition metal hydrides are of great interest in chemistry because of their reactivity and their potential use as catalysts for hydrogenation. Among other available techniques, structural properties in transition metal (TM) complexes are often probed by NMR spectroscopy. In this paper we will show that it is possible to establish a viable methodological strategy in the context of density func...

Journal: :The Journal of chemical physics 2010
Y Kim E Abou-Hamad A Rubio T Wågberg A V Talyzin D Boesch S Aloni A Zettl D E Luzzi C Goze-Bac

The understanding and control of the magnetic properties of carbon-based materials is of fundamental relevance in applications in nano- and biosciences. Ring currents do play a basic role in those systems. In particular the inner cavities of nanotubes offer an ideal environment to investigate the magnetism of synthetic materials at the nanoscale. Here, by means of (13)C high resolution NMR of e...

2009
T. Thonhauser D. Ceresoli Arash A. Mostofi Nicola Marzari David Vanderbilt R. Resta

T. Thonhauser, 2, ∗ D. Ceresoli, Arash A. Mostofi, † Nicola Marzari, David Vanderbilt, and R. Resta Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27109, USA. Department of Materials Science and Engineering, MIT, Cambridge, Massachusetts 02139, USA. Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA. Dipartimento di Fisica Te...

2017
Leila Kalantari Peter Blaha Khoong Hong Khoo Robert Laskowski

Density functional theory (DFT) calculations of the magnetic shielding for solid state nuclear magnetic resonance (NMR) provide an important contribution for the understanding of experimentally observed signals. In this work, we present calculations of the Y NMR shielding in intermetallic compounds (YMg, YT, YTX, YT2X, YT2X2, Y2TB6, and Y2TSi3 where T represents various transition metals and X ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید