NMR spectroscopy of citrate in solids: Cross-polarization kinetics in weakly coupled systems

Jian Feng, Young Jae Lee, James D. Kubicki, Richard J. Reeder, Brian L. Phillips

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Solid-state NMR spectroscopy is a potentially powerful method for obtaining molecular level structural information crucial for understanding the specific relationship between calcite crystals and occluded organic molecules that are important in biomineralization and biomimetic materials. In this work, a method is developed based on cross-polarization/magic angle spinning (CP/MAS) NMR to measure the heteronuclear distances and obtain structural information for large intracrystalline citrate defects in a synthetic calcite/citrate composite. Using compounds with well-characterized crystal structures, Mg(II) citrate and Sr(II) citrate, a correlation is established between T15, the CP time, and M2 15, the van Vleck heteronuclear dipolar second moment, which contains distance and structural information. This correlation is supported by peak assignments obtained from calculations of the 13C chemical shifts for crystalline Mg(II) citrate. On the basis of T IS -1 versus M2 15 correlation, measurement of TI5 for carbonate ions associated with citrate defects in a cakite(13C-enriched)/citrate coprecipitate yields an estimate for the distance between citrate and the nearest carbonate carbon that indicates close spatial proximity and provides useful constraints for future computational study. The applicability of TIS versus M 2 15 correlations to other weakly coupled spin-1/2 systems is discussed in terms of the effects of 1H homonuclear dipolar coupling, using the CP kinetics of Zn(II) dihydroxybenzoate and kaolinite for comparison. The results suggest a limited range of correlation constants and indicate that quantitative information can be obtained from CP/MAS kinetics obtained under similar experimental conditions.

Original languageEnglish
Pages (from-to)408-417
Number of pages10
JournalMagnetic Resonance in Chemistry
Volume46
Issue number5
DOIs
Publication statusPublished - 2008 May 1

Fingerprint

Magic angle spinning
cross polarization
Calcite
citrates
Citric Acid
Nuclear magnetic resonance spectroscopy
Carbonates
Biomimetic materials
Polarization
Biomineralization
Defects
nuclear magnetic resonance
Kinetics
Kaolinite
kinetics
Chemical shift
spectroscopy
Crystal structure
Nuclear magnetic resonance
Crystalline materials

Keywords

  • C
  • Si
  • H
  • Calcite
  • Citrate
  • Cross-polarization
  • DFT
  • NMR
  • Second moment
  • T

ASJC Scopus subject areas

  • Chemistry(all)
  • Physical and Theoretical Chemistry
  • Spectroscopy

Cite this

NMR spectroscopy of citrate in solids : Cross-polarization kinetics in weakly coupled systems. / Feng, Jian; Lee, Young Jae; Kubicki, James D.; Reeder, Richard J.; Phillips, Brian L.

In: Magnetic Resonance in Chemistry, Vol. 46, No. 5, 01.05.2008, p. 408-417.

Research output: Contribution to journalArticle

Feng, Jian ; Lee, Young Jae ; Kubicki, James D. ; Reeder, Richard J. ; Phillips, Brian L. / NMR spectroscopy of citrate in solids : Cross-polarization kinetics in weakly coupled systems. In: Magnetic Resonance in Chemistry. 2008 ; Vol. 46, No. 5. pp. 408-417.
@article{ebfb4c50dcab43c0b40b88c21ee2a40b,
title = "NMR spectroscopy of citrate in solids: Cross-polarization kinetics in weakly coupled systems",
abstract = "Solid-state NMR spectroscopy is a potentially powerful method for obtaining molecular level structural information crucial for understanding the specific relationship between calcite crystals and occluded organic molecules that are important in biomineralization and biomimetic materials. In this work, a method is developed based on cross-polarization/magic angle spinning (CP/MAS) NMR to measure the heteronuclear distances and obtain structural information for large intracrystalline citrate defects in a synthetic calcite/citrate composite. Using compounds with well-characterized crystal structures, Mg(II) citrate and Sr(II) citrate, a correlation is established between T15, the CP time, and M2 15, the van Vleck heteronuclear dipolar second moment, which contains distance and structural information. This correlation is supported by peak assignments obtained from calculations of the 13C chemical shifts for crystalline Mg(II) citrate. On the basis of T IS -1 versus M2 15 correlation, measurement of TI5 for carbonate ions associated with citrate defects in a cakite(13C-enriched)/citrate coprecipitate yields an estimate for the distance between citrate and the nearest carbonate carbon that indicates close spatial proximity and provides useful constraints for future computational study. The applicability of TIS versus M 2 15 correlations to other weakly coupled spin-1/2 systems is discussed in terms of the effects of 1H homonuclear dipolar coupling, using the CP kinetics of Zn(II) dihydroxybenzoate and kaolinite for comparison. The results suggest a limited range of correlation constants and indicate that quantitative information can be obtained from CP/MAS kinetics obtained under similar experimental conditions.",
keywords = "C, Si, H, Calcite, Citrate, Cross-polarization, DFT, NMR, Second moment, T",
author = "Jian Feng and Lee, {Young Jae} and Kubicki, {James D.} and Reeder, {Richard J.} and Phillips, {Brian L.}",
year = "2008",
month = "5",
day = "1",
doi = "10.1002/mrc.2191",
language = "English",
volume = "46",
pages = "408--417",
journal = "Organic Magnetic Resonance",
issn = "0030-4921",
publisher = "John Wiley and Sons Ltd",
number = "5",

}

TY - JOUR

T1 - NMR spectroscopy of citrate in solids

T2 - Cross-polarization kinetics in weakly coupled systems

AU - Feng, Jian

AU - Lee, Young Jae

AU - Kubicki, James D.

AU - Reeder, Richard J.

AU - Phillips, Brian L.

PY - 2008/5/1

Y1 - 2008/5/1

N2 - Solid-state NMR spectroscopy is a potentially powerful method for obtaining molecular level structural information crucial for understanding the specific relationship between calcite crystals and occluded organic molecules that are important in biomineralization and biomimetic materials. In this work, a method is developed based on cross-polarization/magic angle spinning (CP/MAS) NMR to measure the heteronuclear distances and obtain structural information for large intracrystalline citrate defects in a synthetic calcite/citrate composite. Using compounds with well-characterized crystal structures, Mg(II) citrate and Sr(II) citrate, a correlation is established between T15, the CP time, and M2 15, the van Vleck heteronuclear dipolar second moment, which contains distance and structural information. This correlation is supported by peak assignments obtained from calculations of the 13C chemical shifts for crystalline Mg(II) citrate. On the basis of T IS -1 versus M2 15 correlation, measurement of TI5 for carbonate ions associated with citrate defects in a cakite(13C-enriched)/citrate coprecipitate yields an estimate for the distance between citrate and the nearest carbonate carbon that indicates close spatial proximity and provides useful constraints for future computational study. The applicability of TIS versus M 2 15 correlations to other weakly coupled spin-1/2 systems is discussed in terms of the effects of 1H homonuclear dipolar coupling, using the CP kinetics of Zn(II) dihydroxybenzoate and kaolinite for comparison. The results suggest a limited range of correlation constants and indicate that quantitative information can be obtained from CP/MAS kinetics obtained under similar experimental conditions.

AB - Solid-state NMR spectroscopy is a potentially powerful method for obtaining molecular level structural information crucial for understanding the specific relationship between calcite crystals and occluded organic molecules that are important in biomineralization and biomimetic materials. In this work, a method is developed based on cross-polarization/magic angle spinning (CP/MAS) NMR to measure the heteronuclear distances and obtain structural information for large intracrystalline citrate defects in a synthetic calcite/citrate composite. Using compounds with well-characterized crystal structures, Mg(II) citrate and Sr(II) citrate, a correlation is established between T15, the CP time, and M2 15, the van Vleck heteronuclear dipolar second moment, which contains distance and structural information. This correlation is supported by peak assignments obtained from calculations of the 13C chemical shifts for crystalline Mg(II) citrate. On the basis of T IS -1 versus M2 15 correlation, measurement of TI5 for carbonate ions associated with citrate defects in a cakite(13C-enriched)/citrate coprecipitate yields an estimate for the distance between citrate and the nearest carbonate carbon that indicates close spatial proximity and provides useful constraints for future computational study. The applicability of TIS versus M 2 15 correlations to other weakly coupled spin-1/2 systems is discussed in terms of the effects of 1H homonuclear dipolar coupling, using the CP kinetics of Zn(II) dihydroxybenzoate and kaolinite for comparison. The results suggest a limited range of correlation constants and indicate that quantitative information can be obtained from CP/MAS kinetics obtained under similar experimental conditions.

KW - C

KW - Si

KW - H

KW - Calcite

KW - Citrate

KW - Cross-polarization

KW - DFT

KW - NMR

KW - Second moment

KW - T

UR - http://www.scopus.com/inward/record.url?scp=51449105241&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=51449105241&partnerID=8YFLogxK

U2 - 10.1002/mrc.2191

DO - 10.1002/mrc.2191

M3 - Article

C2 - 18306443

AN - SCOPUS:51449105241

VL - 46

SP - 408

EP - 417

JO - Organic Magnetic Resonance

JF - Organic Magnetic Resonance

SN - 0030-4921

IS - 5

ER -