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Title: Structural relationships in rare earth-transition metal hydrides

Abstract

Several structural types of form AB/sub 2/, AB/sub 3/, A/sub 2/B/sub 7/, and AB/sub 5/ (A = rare earth, B = transition metal) are known to be closely related, with local environments which are very similar among the different compounds. Based on these relationships, we suggest that hydride phases A/sub l/B/sub m/H/sub n/ should be related according to the relationships n(AB/sub 3/) = 1/3n(AB/sub 5/) + 2/3n(AB/sub 2/) and n(A/sub 2/B/sub 7/) = n(AB/sub 5/) + n(AB/sub 2/) where the n(AB/sub m/) are observed hydrogen phase concentrations. It is shown that the phases observed in pressure-composition isotherms for AB/sub 3/ and A/sub 2/B/sub 7/ systems can be understood from this viewpoint. A discussion is given of the maximum hydrogen concentration possible in the compounds having these structure types.

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Laboratory (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
6588678
Alternate Identifier(s):
OSTI ID: 6588678
Report Number(s):
CONF-800402-20
Journal ID: ISSN 0022-5088
DOE Contract Number:
W-31-109-ENG-38
Resource Type:
Conference
Resource Relation:
Journal Volume: 74; Journal Issue: 1; Conference: International symposium on the properties and applications of metal hydrides, Colorado Springs, CO, USA, 7 Apr 1980
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; HYDRIDES; PHASE STUDIES; RARE EARTH COMPOUNDS; TRANSITION ELEMENT COMPOUNDS; HYDROGEN COMPOUNDS 360102* -- Metals & Alloys-- Structure & Phase Studies

Citation Formats

Dunlap, B. D., Viccaro, P. J., and Shenoy, G. K. Structural relationships in rare earth-transition metal hydrides. United States: N. p., 1980. Web. doi:10.1016/0022-5088(80)90075-2.
Dunlap, B. D., Viccaro, P. J., & Shenoy, G. K. Structural relationships in rare earth-transition metal hydrides. United States. doi:10.1016/0022-5088(80)90075-2.
Dunlap, B. D., Viccaro, P. J., and Shenoy, G. K. Tue . "Structural relationships in rare earth-transition metal hydrides". United States. doi:10.1016/0022-5088(80)90075-2. https://www.osti.gov/servlets/purl/6588678.
@article{osti_6588678,
title = {Structural relationships in rare earth-transition metal hydrides},
author = {Dunlap, B. D. and Viccaro, P. J. and Shenoy, G. K.},
abstractNote = {Several structural types of form AB/sub 2/, AB/sub 3/, A/sub 2/B/sub 7/, and AB/sub 5/ (A = rare earth, B = transition metal) are known to be closely related, with local environments which are very similar among the different compounds. Based on these relationships, we suggest that hydride phases A/sub l/B/sub m/H/sub n/ should be related according to the relationships n(AB/sub 3/) = 1/3n(AB/sub 5/) + 2/3n(AB/sub 2/) and n(A/sub 2/B/sub 7/) = n(AB/sub 5/) + n(AB/sub 2/) where the n(AB/sub m/) are observed hydrogen phase concentrations. It is shown that the phases observed in pressure-composition isotherms for AB/sub 3/ and A/sub 2/B/sub 7/ systems can be understood from this viewpoint. A discussion is given of the maximum hydrogen concentration possible in the compounds having these structure types.},
doi = {10.1016/0022-5088(80)90075-2},
journal = {},
number = 1,
volume = 74,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1980},
month = {Tue Jan 01 00:00:00 EST 1980}
}

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