Investigation of the magnetic field dependence of CIDNP in multi-nuclear radical pairs. Part II. Photoreaction of tyrosine and comparison of model calculation with experimental data
Investigation of the magnetic field dependence of CIDNP in multi-nuclear radical pairs. Part II. Photoreaction of tyrosine and comparison of model calculation with experimental data
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多核自由基对中 CIDNP 的磁场依赖性研究。 第二部分：酪氨酸的光反应 酪氨酸的光反应以及模型计算与实验数据的比较
DOI：
10.1039/b304086k
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发表时间：
2003-01-01
影响因子：
3.3
通讯作者：
Sagdeev, RZ
中科院分区：
文献类型：
--
作者：
Ivanov, KL;Vieth, HM;Sagdeev, RZ
在0-7 T的磁场范围内，测量了2，2 ′-联吡啶与酪氨酸光反应产生的化学诱导动态核极化（CIDNP）的磁场依赖性，并与数值模拟结果进行了比较.实验采用可变偏振场和固定检测场之间的场循环。CIDNP的模拟是基于孪生反应的绿色函数理论中的低粘度近似。考虑了绝热场变化和RF激励脉冲持续时间的影响。在整个场范围内的理论和实验之间的良好协议被发现为净和多重极化观察到在三个耦合自旋对（CH 2质子在β-位置的酪氨酸，H2，3和H5，6质子的环）。该理论模型和实验技术的广泛适用性使其可用于表征短寿命反应中间体，并适用于蛋白质表面结构和蛋白质折叠过程的CIDNP研究。
The magnetic field dependence of chemically induced dynamic nuclear polarization (CIDNP) formed in the photoreaction of excited 2,2'-dipyridyl and tyrosine is measured in the field range 0-7 T and compared with numerical simulations. The experiments employ field cycling between a variable field of polarization and a fixed field of detection. The simulations of CIDNP are based on the low-viscosity approximation in the Green function theory of geminate reactions. The effects of adiabatic field change and of duration of the RF excitation pulse are taken into account. Good agreement between theory and experiment in the whole field range is found for both net and multiplet polarization as observed in three coupled spin pairs (CH2 protons in beta-position of tyrosine, H2,3 and H5,6 protons of its ring). The wide applicability of the theoretical model and the experimental technique make them useful for the characterization of shortlived reaction intermediates and are suited to CIDNP studies of protein surface structure and folding process of protein.