Density functional calculations of the 29Si and 27 Al MAS NMR spectra of the zeolite mazzite: analysis of geometrical and electronic effects
Article Abstract:
Research was conducted to examine the 29Si and 27Al NMR chemical shifts of the two crystallographic sites of the zeolite mazzite from the NMR shielding tensors by the SOS-DFPT approach. The NMR shielding constants of the Si sites and models, wherein each T site in turn was substituted by aluminum, were measured. Results reveal that a good description of the relative position of the NMR peaks is derived using clusters including two coordination shells around each site.
Publication Name: Journal of Physical Chemistry B
Subject: Chemicals, plastics and rubber industries
ISSN: 1520-6106
Year: 1999
User Contributions:
Comment about this article or add new information about this topic:
Origin of the lone pair of alpha-PbO from density functional theory calculations
Article Abstract:
A study was conducted to analyze ab initio computations utilizing density functional theory within the local density approximation on PbO during the alpha-phase and idealized CsCl structure. An interactive matrix diagonalization technique was utilized to solve Kohn-Sham equations. Results indicated that the stabilization of the alpha-PbO structure over the CsCl structure correlated with the mixing of lead 6p states into the filled antibonding O 2p and Pb 6s states.
Publication Name: Journal of Physical Chemistry B
Subject: Chemicals, plastics and rubber industries
ISSN: 1520-6106
Year: 1999
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Vibrational force field calculations of ara-A. Application to the analysis of its infrared and Raman spectra. Vibrational analysis of amino acids and short peptides in hydrated media. I. L-glycine and L-leucine
- Abstracts: Time-domain calculations of the infrared and polarized Raman spectra of in aqueous solution. DFT vibrational calculations of rhodamine 6G adsorbed on silver: Analysis of tip-enhanced Raman spectroscopy
- Abstracts: Detecting gas hydrate behavior in crude oil using NMR. Single- and triple-quantum 27Al MAS NMR study of the thermal transformation of kaolinite
- Abstracts: Density functional theory calculations for simple oxametallacycles: trends across the periodic table. Correlating electronic properties of bimetallic surfaces with reaction pathways of [C.sub.2] hydrocarbons
- Abstracts: Ab initio prediction of tryptophan fluorescence quenching by protein electric field enabled electron transfer