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Title: Solution State Structure Determination of Silicate Oligomers by 29Si NMR Spectroscopy and Molecular Modeling

Abstract

Evidence for nine new solution state silicate oligomers has been discovered by 29Si NMR homonuclear correlation experiments of 29Si-enriched samples. In addition to enhancing signal sensitivity, the isotopic enrichment increases the probability of the 29Si–29Si two-bond scalar couplings that are necessary for the observation of internuclear correlations in 2-D experiments. The proposed assignments are validated by comparisons of experimental and simulated crosspeaks obtained with high digital resolution. The internuclear connectivity indicated by the NMR data suggests that several of these oligomers can have multiple stereoisomers, including conformers and/or diastereomers. The stability of these oligomers and their possible stereoisomers have been investigated by electronic structure calculations.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
877576
Report Number(s):
PNNL-SA-46407
Journal ID: ISSN 0002-7863; JACSAT; 3600a; KP1301020; TRN: US200608%%425
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Chemical Society, 128(7):2324-2335; Journal Volume: 128; Journal Issue: 7
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; STRUCTURAL CHEMICAL ANALYSIS; ELECTRONIC STRUCTURE; SILICATES; NUCLEAR MAGNETIC RESONANCE; Environmental Molecular Sciences Laboratory

Citation Formats

Cho, Herman M., Felmy, Andrew R., Craciun, Raluca, Keenum, Johnathan P., Shah, Neil K., and Dixon, David A.. Solution State Structure Determination of Silicate Oligomers by 29Si NMR Spectroscopy and Molecular Modeling. United States: N. p., 2006. Web. doi:10.1021/ja0559202.
Cho, Herman M., Felmy, Andrew R., Craciun, Raluca, Keenum, Johnathan P., Shah, Neil K., & Dixon, David A.. Solution State Structure Determination of Silicate Oligomers by 29Si NMR Spectroscopy and Molecular Modeling. United States. doi:10.1021/ja0559202.
Cho, Herman M., Felmy, Andrew R., Craciun, Raluca, Keenum, Johnathan P., Shah, Neil K., and Dixon, David A.. Wed . "Solution State Structure Determination of Silicate Oligomers by 29Si NMR Spectroscopy and Molecular Modeling". United States. doi:10.1021/ja0559202.
@article{osti_877576,
title = {Solution State Structure Determination of Silicate Oligomers by 29Si NMR Spectroscopy and Molecular Modeling},
author = {Cho, Herman M. and Felmy, Andrew R. and Craciun, Raluca and Keenum, Johnathan P. and Shah, Neil K. and Dixon, David A.},
abstractNote = {Evidence for nine new solution state silicate oligomers has been discovered by 29Si NMR homonuclear correlation experiments of 29Si-enriched samples. In addition to enhancing signal sensitivity, the isotopic enrichment increases the probability of the 29Si–29Si two-bond scalar couplings that are necessary for the observation of internuclear correlations in 2-D experiments. The proposed assignments are validated by comparisons of experimental and simulated crosspeaks obtained with high digital resolution. The internuclear connectivity indicated by the NMR data suggests that several of these oligomers can have multiple stereoisomers, including conformers and/or diastereomers. The stability of these oligomers and their possible stereoisomers have been investigated by electronic structure calculations.},
doi = {10.1021/ja0559202},
journal = {Journal of the American Chemical Society, 128(7):2324-2335},
number = 7,
volume = 128,
place = {United States},
year = {Wed Feb 22 00:00:00 EST 2006},
month = {Wed Feb 22 00:00:00 EST 2006}
}
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