DETERMINATION OF CHEMICAL-SHIFT TENSOR ORIENTATIONS IN METHYLENE GROUPS BY SEPARATED-LOCAL-FIELD NMR

被引：35

作者：

SCHMIDT-ROHR, K

WILHELM, M

JOHANSSON, A

SPIESS, HW

机构：

[1] MAX PLANCK INST POLYMER RES, POSTFACH 3148, W-6500 MAINZ, GERMANY

[2] UNIV UPPSALA, INST CHEM, S-75121 UPPSALA, SWEDEN

来源：

MAGNETIC RESONANCE IN CHEMISTRY | 1993年 / 31卷 / 04期

关键词：

SEPARATED-LOCAL-FIELD NMR; CHEMICAL-SHIFT TENSOR ORIENTATIONS; POLY(ETHYLENE OXIDE);

D O I：

10.1002/mrc.1260310408

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The C-13 chemical-shift tensor orientations in the OCH2CH2O moieties of poly(ethylene oxide) (PEO) and poly(ethylene terephthalate) (PET) were determined by means of H-1-C-13 separated-local-field NMR spectroscopy, and the literature values for the shift tensors in polyethylene (PE) and polyoxymethylene (POM) were improved. An angular resolution of +/- 4-degrees was attained on standard equipment with 90-degrees pulse lengths exceeding 4 mus. Relatively high uniformity of the methylene tensor orientations, complying with local molecular symmetry, was found.

引用

页码：352 / 356

页数：5

共 27 条

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