Refining siliceous zeolite framework structures with 29Si 2D J-resolved NMR spectroscopy

被引：0

作者：

Srivastava, Deepansh J. ^{[1
]}

Venetos, Maxwell C. ^{[2
]}

McCarthy-Carney, Lexi ^{[3
]}

Baltisberger, Jay H. ^{[4
]}

Grandinetti, Philip J. ^{[3
]}

Brouwer, Darren ^{[5
]}

机构：

[1] Hyperfine Inc, Guilford, CT USA

[2] Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA USA

[3] Ohio State Univ, Dept Chem, Columbus, OH 43210 USA

[4] Wacker Chem Corp, Ann Arbor, MI USA

[5] Redeemer Univ, Dept Chem, Ancaster, ON, Canada

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2024年 / 27卷 / 01期

基金：

美国国家科学基金会; 加拿大自然科学与工程研究理事会;

关键词：

AB-INITIO CALCULATIONS; SOLID-STATE; MAGIC-ANGLE; CRYSTAL-STRUCTURE; 2-DIMENSIONAL NMR; CHEMICAL-SHIFTS; O-17; REFINEMENT; SPECTRA; CRYSTALLOGRAPHY;

D O I：

10.1039/d4cp03530e

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A modified shifted-echo PIETA pulse sequence is developed to acquire natural abundance 29Si 2D J-resolved spectra in crystalline silicates. The sequence is applied to the highly siliceous zeolites Sigma-2 and ZSM-12. The 2D J-resolved spectra are used to develop a silicate framework structure refinement strategy based on Si-O, O-O, and Si-Si distance restraints and analytical relationships between local structure and 29Si chemical shifts and geminal 2JSi-O-Si couplings. The refinement of the Sigma-2 structure showed that the Si-O and O-O distances were in excellent agreement with the single-crystal X-ray diffraction (SCXRD) data. The refinement of the ZSM-12 structure, initially determined from synchrotron powder XRD data, highlighted significant improvements in Si-O and O-O distances, and better agreement between calculated and experimental chemical shifts and J-couplings.

引用

页码：419 / 435

页数：17

共 55 条

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