소개글
서울대학교 2021년도 물리분석실험 리포트입니다.
목차
1. Abstract
2. Results
3. Discussion
1) N,N-dimethylacetamide
2) Cis-trans isomerization rate constant
4. Assignment (NMR을 이용한 분자의 polarizability와 dipole moment 측정)
본문내용
1. Abstract
N,N-dimethylacetamide는 amide기 공명 구조의 특징 상 C-N bond의 rotation이 제한되어 cis-trans isomerization의 속도가 일반적인 single bond보다 느리다. 이에 대해 본 실험에서는 FT NMR의 일종인 2D EXSY(Exchange Spectroscopy)를 이용하여 실제 N,N-dimethylacetamide의 cis-trans isomerization의 속도 상수를 분석하였다. 이를 위해, mixing time 0.2, 0.3, 0.4, 0.5, 0.6초에 대해 각 mixing 전후 conformation pair에 대한 intensity를 측정하고 이를 plot하였다. 얻은 선형회귀선을 이용하여cis-trans isomerization의 속도 상수와 오차 범위를 분석하고 문헌값과 비교하여 오차 요인을 분석하였다.
참고 자료
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