scholarly journals Temperature effects in first-principles solid state calculations of the chemical shielding tensor made simple

2014 ◽  
Vol 141 (13) ◽  
pp. 134113 ◽  
Author(s):  
Bartomeu Monserrat ◽  
Richard J. Needs ◽  
Chris J. Pickard
Keyword(s):  
Solid State ◽  
First Principles ◽  
Temperature Effects ◽  
Chemical Shielding ◽  
Shielding Tensor

Phosphorus-31 solid-state nuclear magnetic resonance study of monophosphazenes

1989 ◽  
Vol 67 (3) ◽  
pp. 454-459 ◽  
Author(s):  
William P. Power ◽  
Roderick E. Wasylishen ◽  
Ronald D. Curtis
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Solid State ◽  
Magnetic Resonance ◽  
Dipolar Coupling ◽  
Nuclear Magnetic Resonance Study ◽  
Coupling Constants ◽  
Chemical Shielding ◽  
Spin Pair ◽  
Shielding Tensor ◽  
Nuclear Magnetic

Simultaneous observation of anisotropic chemical shielding and dipolar coupling in polycrystalline monophosphazenes has been used to obtain information on the 31P–14N spin pair. Phosphorus-31 chemical shielding tensor components have been determined; the most shielded component was found to lie along the P=N bond. The 31P–14N dipolar coupling constants have provided P=N bond lengths from powder samples, equivalent for all compounds within experimental error; the value obtained for N–(triphenylphosphoranylidene)-aniline is in excellent agreement with that obtained in a recent X-ray diffraction study. Features of crystallographic significance have been determined from the solid-state nuclear magnetic resonance spectra for two of the compounds without resorting to diffraction techniques. Information on the magnitude and orientation of the 14N electric field gradient tensor has been inferred from 31P MAS spectra and abinitio calculations. Keywords: monophosphazenes, dipolar nmr, 31P chemical shielding anisotropies, solid-state nmr.

31P chemical shielding as a function of bond angle: phosphorus chemical shielding surface of phosphinoborane R2PBR'2

1999 ◽  
Vol 77 (11) ◽  
pp. 1951-1961 ◽  
Author(s):  
Michael JT Ditty ◽  
William P Power
Keyword(s):  
Solid State ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Principal Components ◽  
Bond Angle ◽  
Good Description ◽  
Chemical Shielding ◽  
Orbital Theory ◽  
Shielding Tensor ◽  
Theory Calculation

The phosphorus chemical shielding surface of phosphinoborane R2PBR'2 has been investigated via molecular orbital theory calculation and experimental measurement of selected derivatives. Ab initio calculations of phosphorus chemical shielding tensors were determined for the phosphinoboranes H2PBH2 and (CH3)2PB(CH3)2. Changes in the angle from planarity, i.e., that between the P-BR'2 plane and the bisector of the RPR angle, are reflected in the orientations and magnitudes of the three principal components of the phosphorus chemical shielding tensor. To determine the validity of the calculated phosphorus chemical shielding surface, three phosphinoborane compounds with different angles from planarity were synthesized and studied by solid-state 31P NMR spectroscopy. The 31P NMR powder patterns provided experimental magnitudes of the principal components of the phosphorus chemical shielding tensor for each compound, which compared well to the calculated predictions; where orientations of these tensors could be determined experimentally, they also agreed well with the calculated results. The combined experimental and theoretical results provide a good description of the effects on changes in bond angle on phosphorus chemical shielding as the molecule is distorted from a planar to folded geometry.Key words: chemical shielding, solid-state NMR, phoshinoborane, ab initio calculations.

First principles study on the electronic structure properties of Keggin polyoxometalates on Carbon substrates for solid-state devices

2017 ◽  
Vol 136 (2) ◽  
Author(s):  
Jesús Muñiz ◽  
Christian Celaya ◽  
Ana Mejía-Ozuna ◽  
Ana Karina Cuentas-Gallegos ◽  
L. M. Mejía-Mendoza ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Solid State ◽  
First Principles ◽  
First Principles Study ◽  
Solid State Devices ◽  
Carbon Substrates ◽  
Structure Properties

scholarly journals Ion Dynamics and CO2 Absorption Properties of Nb-, Ta-, and Y-Doped Li2ZrO3 Studied by Solid-State NMR, Thermogravimetry, and First-Principles Calculations

2017 ◽  
Vol 121 (40) ◽  
pp. 21877-21886 ◽  
Author(s):  
Matthew T. Dunstan ◽  
Hannah Laeverenz Schlogelhofer ◽  
John M. Griffin ◽  
Matthew S. Dyer ◽  
Michael W. Gaultois ◽  
...  
Keyword(s):  
Solid State ◽  
First Principles ◽  
Solid State Nmr ◽  
Co2 Absorption ◽  
Ion Dynamics ◽  
First Principles Calculations ◽  
Absorption Properties
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