How floppy modes give rise to adsorption sites in zeolites

被引：88

作者：

Hammonds, KD ^{[1
]}

Deng, H ^{[1
]}

Heine, V ^{[1
]}

Dove, MT ^{[1
]}

机构：

[1] UNIV CAMBRIDGE,DEPT EARTH SCI,CAMBRIDGE CB2 3EQ,ENGLAND

来源：

PHYSICAL REVIEW LETTERS | 1997年 / 78卷 / 19期

关键词：

DISPLACIVE PHASE-TRANSITIONS; FRAMEWORK STRUCTURE; ENVIRONMENT;

D O I：

10.1103/PhysRevLett.78.3701

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The question as to how zeolites are able to hold tightly bound ions is answered. We show that zeolite frameworks can support whole bands of rigid unit modes (floppy modes) in k space and hence show that localized rigid unit modes can form within such frameworks that do not distort the constituent tetrahedra to any significant degree. It is these local modes that enable cations at certain sites to pull the framework-with virtually zero cost in elastic energy-in such a way that oxygen-cation bonding distances become exactly optimal for the cation concerned.

引用

页码：3701 / 3704

页数：4

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