Neutron powder diffraction study of potassium clusters in zeolite K-LTA

被引：27

作者：

Ikeda, T

Kodaira, T

Izumi, F

Kamiyama, T

Ohshima, K

机构：

[1] Natl Inst Res Inorgan Mat, Tsukuba, Ibaraki 3050044, Japan

[2] Natl Inst Mat & Chem Res, Tsukuba, Ibaraki 3058565, Japan

[3] Univ Tsukuba, Inst Mat Sci, Tsukuba, Ibaraki 3058573, Japan

来源：

CHEMICAL PHYSICS LETTERS | 2000年 / 318卷 / 1-3期

关键词：

D O I：

10.1016/S0009-2614(00)00017-8

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：

The crystal structures of K-doped K-LTA below and above the Curie temperature of 8 K were analyzed by neutron powder diffraction on the basis of space group F23. We found alternate ordering of Si and Al in a distorted framework and different K clusters in two kinds of alpha-cages. Additional K+ ions are distributed mainly in four- and eight-membered rings of the framework and partially occupy the center of an alpha-cage. K+ ions near the center of a six-membered ring form two kinds of tetrahedral assemblies occupied statistically. Our structural data suggest that the K clusters in the adjacent alpha-cages have different magnetic moments. This is consistent with a spontaneous magnetic moment, which is observable even if the K clusters interact antiferromagnetically. (C) 2000 Elsevier Science B.V. All rights reserved.

引用

页码：93 / 101

页数：9

共 21 条

[1] THE STRUCTURE OF DEHYDRATED NA ZEOLITE A (SI/AL=1.09) BY NEUTRON PROFILE REFINEMENT [J].

ADAMS, JM ;

HASELDEN, DA ;

HEWAT, AW .

JOURNAL OF SOLID STATE CHEMISTRY, 1982, 44 (02) :245-253

[2] THE STRUCTURE OF DEHYDRATED ZEOLITE 3A (SI/AL = 1.01) BY NEUTRON PROFILE REFINEMENT [J].

ADAMS, JM ;

HASELDEN, DA .

JOURNAL OF SOLID STATE CHEMISTRY, 1983, 47 (02) :123-131

[3] LOW-PRESSURE AND TEMPERATURE-DEPENDENT PHASE-TRANSITIONS OF A POTASSIUM EXCHANGED ZEOLITE-A [J].

APPEL, W ;

IHRINGER, J ;

KNORR, K ;

PRANDL, W .

ZEOLITES, 1987, 7 (05) :423-426

[4] THE COMPOSITION DEPENDENCE OF THE STRUCTURE OF POTASSIUM-LOADED ZEOLITE-A - EVOLUTION OF A POTASSIUM SUPERLATTICE [J].

ARMSTRONG, AR ;

ANDERSON, PA ;

EDWARDS, PP .

JOURNAL OF SOLID STATE CHEMISTRY, 1994, 111 (01) :178-189

[5] A STUDY OF SI,AL ORDERING IN THALLIUM ZEOLITE-A BY POWDER NEUTRON-DIFFRACTION [J].

CHEETHAM, AK ;

EDDY, MM ;

JEFFERSON, DA ;

THOMAS, JM .

NATURE, 1982, 299 (5878) :24-26

[6] Structural study of sodium-type zeolite LTA by combination of Rietveld and maximum-entropy methods [J].

Ikeda, T ;

Izumi, F ;

Kodaira, T ;

Kamiyama, T .

CHEMISTRY OF MATERIALS, 1998, 10 (12) :3996-4004

[7]

IKEDA T, IN PRESS MOL CRYST L

[8] Optical studies of nanoscale materials incorporated in the space of zeolite crystals [J].

Ikemoto, Y ;

Nakano, T ;

Nozue, Y ;

Terasaki, O ;

Qiu, S .

MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY, 1997, 48 (1-2) :116-121

[9]

IZUMI F, 1995, RIETVELD METHOD, pCH13

[10] OPTICAL-PROPERTIES OF POTASSIUM CLUSTERS INCORPORATED INTO ZEOLITE LTA [J].

KODAIRA, T ;

NOZUE, Y ;

OHWASHI, S ;

GOTO, T ;

TERASAKI, O .

PHYSICAL REVIEW B, 1993, 48 (16) :12245-12252

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