Israelachvili J, Sjösten J, Eriksson L E, Ehrström M, Gräslund A, Ehrenberg A
Biochim Biophys Acta. 1975 Mar 13;382(2):125-41. doi: 10.1016/0005-2736(75)90171-6.
Electron spin resonance (ESR) spectral line shapes are calculated for a nitroxide spin-labeled molecule undergoing rapid restricted rotations (twisting) about its long molecular axis while simultaneously tumbling within a cone. Explicit expressions are derived for the hyperfine splittings and g-values, as well as for the secular contributions to the motionally modulated linewidths. The present model is useful for analyzing the restricted twisting and tumbling motions, and rotational correlation times, of spin-labeled molecules in bilayers. Simulated spectra compare well with experimental spectra of lecithin bilayers marked with cholestane spin label, over a wide temperature range.
计算了一个氮氧化物自旋标记分子的电子自旋共振（ESR）谱线形状，该分子围绕其长分子轴进行快速受限旋转（扭曲），同时在一个圆锥体内翻滚。推导了超精细分裂和g值的显式表达式，以及对动态调制线宽的长期贡献的表达式。本模型可用于分析双层中自旋标记分子的受限扭曲和翻滚运动以及旋转相关时间。在很宽的温度范围内，模拟光谱与用胆甾烷自旋标记的卵磷脂双层的实验光谱吻合良好。
