NMR 화학적 이동을 이용한 액정 고분자의 구조 연구 = Structural Studies for Loquid Crystalline Polymer Based on nMR Chemical Shifts

다국어 초록 (Multilingual Abstract)

13C NNIR chemical shifts have been computed for selected 12-4(Liquid crystalline polymer) using Gauge-Including Atomic Orbitals(GIAO) at the DFT(Density Function Theory) level. The isotropic 13C chemical shifts are largely insensitive to substituent-induced structural changes. In this study, the isotropic 13C chemical shifts GIRO calculations at the B3LYP/6-31G* levels are sufficiently accurate to aid in experimental peak assignments.
Based on the firm assignment of the C4 and C1s chemical shifts in this study, the analysis of their isotropic 13C NMR chemical shift and temperature will help to determine conformational and dynamics changes during the LC phase transition (solid-to-liquid crystal).
Both of results of GIRO-HF/6-31G* and B3LYP/6-31G* were enough to reproduce the experimental data and explain the intermolecular interactions.
The calculated 13C chemical shift for C4 increases when torsion angle, a, increases from 0?to 90?, while the calculated 13C chemical shift for C1s increases when torsion angle, a ' , increases from 0?to 75? This results imply that the planar structure( a =0? a ' = 0? will be distorted slightly during the LC phase transition.

목차 (Table of Contents)

• 목차
• I. 서론 = 1
• II. 방법 및 계산 = 6
• 1. GIAO 방법 = 6
• 2. NMR 화학적 이동 = 7
• III. 결과 및 고찰 = 10
• IV. 결론 = 36
• V. 참고 문헌 = 37
• Abstract = 40