Microsecond time-scale dynamics from relaxation in the rotating frame: experiments using spin lock with alternating phase
Microsecond time-scale dynamics from relaxation in the rotating frame: experiments using spin lock with alternating phase
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DOI：
10.1016/j.jmr.2004.04.011
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发表时间：
2004-07-01
影响因子：
2.2
通讯作者：
Skrynnikov, NR
中科院分区：
文献类型：
--
作者：
Podkorytov, IS;Skrynnikov, NR
提出了一种由交变相位射频脉冲组成的自旋锁，作为探测微秒时间尺度动力学的一种新技术。使用不同脉冲持续时间t(P)的一系列R-1Rho测量允许确定汇率k(Ex)、涉及交换物种的种群p(A)和p(B)的乘积p(A)p(B)(Deltaomega(Ab))(2)、以及化学位移差Deltaomega(Ab)和自旋锁定场的强度B-1。这种解释是基于根据Redfield理论推导出的R-1Rho的简单解析表达式。将该方法应用于环己烷分子在-9℃下进行椅子到椅子的相互转化。(C)2004 Elsevier Inc.保留所有权利。
A spin lock comprised of radiofrequency pulses with alternating phase, (x)(-x)(x)(-x)..., is proposed as a new technique to probe microsecond time-scale dynamics. A series of R-1rho measurements using different pulse duration t(p) allows one to determine exchange rate, k(ex), the product p(a)p(b) (Deltaomega(ab))(2) involving populations of the exchanging species, p(a) and p(b), together with chemical shift difference, Deltaomega(ab), and the strength of the spin-lock field, B-1. The interpretation is based on simple analytical expression for R-1rho derived on the basis of Redfield theory. The application of the method is demonstrated for partially deuterated molecule of cyclohexane undergoing chair-to-chair interconversion at -9 degreesC. (C) 2004 Elsevier Inc. All rights reserved.