### 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

*Concepts in Magnetic Resonance*,

*8*(4), 229-249.

**Quantitative analysis of total correlation spectra : Application to small biomolecules.** / Fogolari, F.; Esposito, Gennaro; Cattarinussi, S.; Viglino, P.

Research output: Contribution to journal › Article

*Concepts in Magnetic Resonance*, vol. 8, no. 4, pp. 229-249.

}

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

VL - 8

SP - 229

EP - 249

JO - Concepts in Magnetic Resonance

JF - Concepts in Magnetic Resonance

SN - 1043-7347

IS - 4

ER -