Abstract
The peak intensities of total correlation spectra are intimately related to J-coupling constants, which in turn are related to local geometry. Knowledge of J values is therefore useful in determining molecular structure. In the past, the complexity of the time development of total correlation cross-peaks has hindered their use in extracting structural information. This paper reviews the relevant quantum-mechanical equations. The series expansion of the density matrix for the most general spin-1/2 system undergoing isotropic mixing offers a convenient approximation that can be exploited to evaluate the extent of net transfer as a function of J values. A method for evaluating J-coupling constants from total correlation spectra of small biomolecules is presented as an application and as an illustration of the theory. Peak amplitude quantitation of short-mixing-time spectra provides tentative estimates of scalar couplings (accurate up to the third order of the series expansion as a function of mixing time). These estimates can be further refined by fitting the experimental data with theoretical transfers obtained by a full density matrix calculation. An experimental illustration of the method is given for a nucleic acid and a coenzyme system, although the conclusions should hold for every similar spin system.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 229-249 |
| Number of pages | 21 |
| Journal | Concepts in Magnetic Resonance |
| Volume | 8 |
| Issue number | 4 |
| State | Published - Dec 1 1996 |
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ASJC Scopus subject areas
- Chemistry(all)
- Spectroscopy
- Physical and Theoretical Chemistry
Cite this
Quantitative analysis of total correlation spectra : Application to small biomolecules. / Fogolari, F.; Esposito, Gennaro; Cattarinussi, S.; Viglino, P.
In: Concepts in Magnetic Resonance, Vol. 8, No. 4, 01.12.1996, p. 229-249.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Quantitative analysis of total correlation spectra
T2 - Application to small biomolecules
AU - Fogolari, F.
AU - Esposito, Gennaro
AU - Cattarinussi, S.
AU - Viglino, P.
PY - 1996/12/1
Y1 - 1996/12/1
N2 - The peak intensities of total correlation spectra are intimately related to J-coupling constants, which in turn are related to local geometry. Knowledge of J values is therefore useful in determining molecular structure. In the past, the complexity of the time development of total correlation cross-peaks has hindered their use in extracting structural information. This paper reviews the relevant quantum-mechanical equations. The series expansion of the density matrix for the most general spin-1/2 system undergoing isotropic mixing offers a convenient approximation that can be exploited to evaluate the extent of net transfer as a function of J values. A method for evaluating J-coupling constants from total correlation spectra of small biomolecules is presented as an application and as an illustration of the theory. Peak amplitude quantitation of short-mixing-time spectra provides tentative estimates of scalar couplings (accurate up to the third order of the series expansion as a function of mixing time). These estimates can be further refined by fitting the experimental data with theoretical transfers obtained by a full density matrix calculation. An experimental illustration of the method is given for a nucleic acid and a coenzyme system, although the conclusions should hold for every similar spin system.
AB - The peak intensities of total correlation spectra are intimately related to J-coupling constants, which in turn are related to local geometry. Knowledge of J values is therefore useful in determining molecular structure. In the past, the complexity of the time development of total correlation cross-peaks has hindered their use in extracting structural information. This paper reviews the relevant quantum-mechanical equations. The series expansion of the density matrix for the most general spin-1/2 system undergoing isotropic mixing offers a convenient approximation that can be exploited to evaluate the extent of net transfer as a function of J values. A method for evaluating J-coupling constants from total correlation spectra of small biomolecules is presented as an application and as an illustration of the theory. Peak amplitude quantitation of short-mixing-time spectra provides tentative estimates of scalar couplings (accurate up to the third order of the series expansion as a function of mixing time). These estimates can be further refined by fitting the experimental data with theoretical transfers obtained by a full density matrix calculation. An experimental illustration of the method is given for a nucleic acid and a coenzyme system, although the conclusions should hold for every similar spin system.
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M3 - Article
AN - SCOPUS:0030529254
VL - 8
SP - 229
EP - 249
JO - Concepts in Magnetic Resonance
JF - Concepts in Magnetic Resonance
SN - 1043-7347
IS - 4
ER -