中国物理B ›› 2008, Vol. 17 ›› Issue (3): 915-920.doi: 10.1088/1674-1056/17/3/029
陈松1, 蔡淑惠1, 陈忠1, 朱小钦2
Chen Song(陈松)a), Zhu Xiao-Qin(朱小钦)b)a), Cai Shu-Hui(蔡淑惠)a), and Chen Zhong(陈忠)a)†
摘要: This paper analyses the heteronuclear Cosy Revamped by Asymmetric Z-gradient Echo Detection pulse sequence. General theoretical expressions of the pulse sequence with arbitrary flip angles were derived by using dipolar field treatment and signals originating from heteronuclear intermolecular single-quantum coherences (iSQCs) in highly-polarized two spin-1/2 systems were mainly discussed in order to find the optimal flip angles. The results show that signals from heteronuclear iSQCs decay slower than those from intermolecular double-quantum coherences or intermolecular zero-quantum coherences. Magical angle experiments validate that the signals are from heteronuclear iSQCs and insensitive to the imperfection of radio-frequency flip angles. All experimental observations are in excellent agreement with theoretical predictions. The quantum-mechanical treatment leads to similar predictions to the dipolar field treatment.
中图分类号: (Nuclear magnetic resonance and relaxation)