摘要
应用规范不变原子轨道（GIAO）方法，考虑分子间的氢键作用，对固体酪氨酸(13)C化学位移屏蔽张量进行了理论模拟，并对本文结果和以前的计算结果与实验值进行了比较．结果表明：对羧基碳，其理论值和实验值的方均根偏差（不考虑氢键作用）为33．4ppm；而考虑氢键作用，其相应的方均根偏差为23ppm．这表明在氨基酸羧基碳的化学屏蔽研究中考虑分子间的氢键作用是很重要的，特别是δ22分量，对氢键作用非常敏感，这和McDermott等人的实验结果基本一致．
By employing the ah initio gauge invariant atomic orbital (GIAO) approach, the influence of hydrogen bonding on the (13)C chemical shift tensor in solid tyrosine was studied. Comparisons of the values of the present paper with those previously calculated and with the experimental results were made. The root - mean - square (rms) error found by comparing the predicted (without hydrogen bonding interaction) and the observed prindpal component for the carboxyl carbon of tyrosine was 33.4ppm; whereas when the hydrogen bonding interaction was introduced, the relevant rms error would be reduced to 23ppm. This dearly highlihts the importance of considering the hydrogen bonding interaction in the study of the (13)C chemical shieldings for the carboxyl carbons, espedally for the δ(22) component, the results presented in this paper also agreed with the observed results of McDermott et al.
出处
《波谱学杂志》
CAS
CSCD
北大核心
1997年第5期419-423,共5页
Chinese Journal of Magnetic Resonance
基金
国家自然科学基金
关键词
酪氨酸
屏蔽张量
氢键
GIAO
碳13
化学位移
Tyrsine, Chemical shielding tensor, Gauge invariant atomic orbital, Hydrogen bonding interaction
