MOLECULAR STRUCTURE FROM DIPOLAR COUPLING
MOLECULAR STRUCTURE FROM DIPOLAR COUPLING
复制标题
偶极耦合的分子结构
DOI：
10.1007/978-94-009-6517-1_7
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发表时间：
1985
影响因子：
2.2
通讯作者：
P. Diehl
中科院分区：
文献类型：
--
作者：
P. Diehl
根据部分取向分子的核磁共振谱确定分子结构的方法首先由Saupe和Engert(1)在1963年提出，它是基于下列有效哈密顿量的最后一项：
$$\Begin{ARRAY}{L}H=-\；{(2\pi)^{-1}}\sum\Limits_i{{\Gamma_i}}{\rm{}}{{\rm{}}_{zi}}(1-\sigma_i^{iso}-\sigma_i^{aniso}){\rm{}}{B_z}\\+\sum\Limits_{i<；J}{\{T_i}_j^{iso}}\Left[{}\Right。{i_{zi}}{i_{zj}}{\rm{}}+\frac{1}{2}{\rm{}}\Left({}\Rm{i}}_i^+{\rm{i}}_j^-{\rm{+i}}_i^-{\rm{i}}_j^+\Left。{}\右)\左。{}\右]\\{\rm{}}{{\rm{T}}_i}_j^{aniso}{\rm{}}\左[{}\右。{{\rm{i}}_{zi}}{\rm{}}{{rm{}}_{zj}}{\rm{-}}\frac{1}{4}{\rm{(I)}_i^+{\rm{i}}_j^i{\rm{+i}}_i^-\，{\rm{i}}_j^+{\rm{)}}\Left。{}\右]{\rm{\}}\end{数组}$$
(1)
其中\({T_i}_j^{iso}{\rm{=}}{{\rm{J}}_i}_j^{iso}{\rm{=}}{{\rm{=}}{{\rm{J}}_{ij}}\)是已知的间接耦合常数，{{t_i}_j^{aniso}{\rm{=}{{\rm{J}_i}_j^{aniso}{\rm{+2}}{{\rm{D}}_{ij}}\)是伪偶极耦合的和，({j_i}_j^{aniso})和偶极或直接耦合Dij。偶极耦合的定义为
$${D_{ij}}=-\FRAC{\MU_0}\hbar{\Gamma_i}{\GAMA_j}}{{8{\pi^2}\FRAC{1}{2}\；{\rm{}}$$
(2)
The determination of molecular structure from NMR spectra of partially oriented molecules, which was first suggested in 1963 by Saupe and Englert (1), is based on the last term of the following effective Hamiltonian:
$$ \begin{array}{l} H = - \;{(2\pi )^{ - 1}}\sum\limits_i {{\gamma _i}} {\rm{ }}{{\rm{I}}_{zi}}(1 - \sigma _i^{iso} - \sigma _i^{aniso}){\rm{ }}{B_z} \\ + \sum\limits_{i < j} {\{ {T_i}_j^{iso}} \left[ {} \right.{I_{zi}}{I_{zj}}{\rm{ }} + \frac{1}{2}{\rm{ }}\left( {} \right.{\rm{I}}_i^ + {\rm{ I}}_j^ - {\rm{ + I}}_i^ - {\rm{ I}}_j^ + \left. {} \right)\left. {} \right] \\ + {\rm{ }}{{\rm{T}}_i}_j^{aniso}{\rm{ }}\left[ {} \right.{{\rm{I}}_{zi}}{\rm{ }}{{\rm{I}}_{zj}}{\rm{ - }}\frac{1}{4}{\rm{(I}}_i^ + {\rm{ I}}_j^i{\rm{ + I}}_i^ - \,{\rm{I}}_j^ + {\rm{)}}\left. {} \right]{\rm{\} }} \\ \end{array} $$
(1)
where \( {T_i}_j^{iso}{\rm{ = }}{{\rm{J}}_i}_j^{iso}{\rm{ = }}{{\rm{J}}_{ij}} \) is the well known indirect coupling constant and \( {T_i}_j^{aniso}{\rm{ = }}{{\rm{J}}_i}_j^{aniso}{\rm{ + 2}}{{\rm{D}}_{ij}} \) is the sum of the pseudo dipolar coupling, \( {J_i}_j^{aniso} \), and the dipolar or direct coupling Dij. The dipolar coupling is defined as
$$ {D_{ij}} = - \frac{{{\mu _0}\hbar {\gamma _i}{\gamma _j}}}{{8{\pi ^2}}}\frac{1}{2}\;{\rm{ }} $$
(2)