图 书 馆
第24讲-高阶效应、动力学和核磁共振时间标度Lecture 24 - Higher-Order Effects, Dynamics, and the NMR Time Scale |
|
| 课程网址: | http://videolectures.net/yalespan125bs2011_mcbride_lec24/ |
| 主讲教师: | J. Michael McBride |
| 开课单位: | 耶鲁大学 |
| 开课时间: | 2014-08-19 |
| 课程语种: | 英语 |
| 中文简介: |  |
| 课程简介: | Because spin-spin splitting depends on electron spin precisely at a nucleus, splitting by a C-13 depends on its orbital’s hybridization. "Higher-order effects" that give complex multiplets for nuclei with similar chemical shifts can be understood in terms of the mixing of wave functions of similar energy. Averaging of chemical shifts or spin-spin splitting may be used to measure the rate of rapid changes in molecular structure, such as changes in conformation or hydrogen bonding. Since the spectroscopic time scale depends on frequency differences, averaging is easier in NMR than in IR. A typical problem involves predicting the NMR spectrum of a compound with diastereotopic groups. In proton decoupling radio frequency irradiation of a particular proton can make it cease to split the NMR signals from nearby protons. |
| 关 键 词: | 高阶效应; 核磁共振; 轨道杂化 |
| 课程来源: | 视频讲座网 |
| 数据采集: | 2021-11-18：zkj |
| 最后编审: | 2021-11-18：zkj |
| 阅读次数: | 69 |