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Title: Pressure enhancement of negative thermal expansion behavior and induced framework softening in Zn(CN){sub 2}.

Abstract

The pressure-dependent structure and functionality of the coordination framework material zinc cyanide, Zn(CN){sub 2}, has been explored using in situ neutron powder diffraction. A third-order Birch-Murnaghan equation of state fit to variable pressure (0?0.6 GPa) data collected at ambient temperature (K{sub 0} = 34.19(21) GPa, K{prime}{sub 0} = -6.0(7)) shows that, contrary to behavior observed for typical materials, the Zn(CN){sub 2} framework becomes more compressible at higher pressures. Variable temperature (50?300 K) data collected at 0.2 and 0.4 GPa indicate that the negative thermal expansion effect in Zn(CN){sub 2} becomes more pronounced at pressure with the coefficient of thermal expansion ({alpha} = dT/{ell}d{ell}) varying by ca. -1 x 10{sup -6} K{sup -1} per 0.2 GPa applied pressure up to an average (50-300 K) value of ?19.42(23) x 10{sup -6} K{sup -1} at 0.4 GPa. Both these unusual phenomena have been linked to increased framework flexibility at high pressure.

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
946414
Report Number(s):
ANL/XSD/JA-59550
Journal ID: ISSN 0002-7863; JACSAT; TRN: US0900952
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Am. Chem. Soc.; Journal Volume: 129; Journal Issue: 33 ; 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMBIENT TEMPERATURE; DIFFRACTION; FLEXIBILITY; NEUTRONS; THERMAL EXPANSION; ZINC

Citation Formats

Chapman, K. W., Chupas, P. J., and X-Ray Science Division. Pressure enhancement of negative thermal expansion behavior and induced framework softening in Zn(CN){sub 2}.. United States: N. p., 2007. Web. doi:10.1021/ja073791e.
Chapman, K. W., Chupas, P. J., & X-Ray Science Division. Pressure enhancement of negative thermal expansion behavior and induced framework softening in Zn(CN){sub 2}.. United States. doi:10.1021/ja073791e.
Chapman, K. W., Chupas, P. J., and X-Ray Science Division. Mon . "Pressure enhancement of negative thermal expansion behavior and induced framework softening in Zn(CN){sub 2}.". United States. doi:10.1021/ja073791e.
@article{osti_946414,
title = {Pressure enhancement of negative thermal expansion behavior and induced framework softening in Zn(CN){sub 2}.},
author = {Chapman, K. W. and Chupas, P. J. and X-Ray Science Division},
abstractNote = {The pressure-dependent structure and functionality of the coordination framework material zinc cyanide, Zn(CN){sub 2}, has been explored using in situ neutron powder diffraction. A third-order Birch-Murnaghan equation of state fit to variable pressure (0?0.6 GPa) data collected at ambient temperature (K{sub 0} = 34.19(21) GPa, K{prime}{sub 0} = -6.0(7)) shows that, contrary to behavior observed for typical materials, the Zn(CN){sub 2} framework becomes more compressible at higher pressures. Variable temperature (50?300 K) data collected at 0.2 and 0.4 GPa indicate that the negative thermal expansion effect in Zn(CN){sub 2} becomes more pronounced at pressure with the coefficient of thermal expansion ({alpha} = dT/{ell}d{ell}) varying by ca. -1 x 10{sup -6} K{sup -1} per 0.2 GPa applied pressure up to an average (50-300 K) value of ?19.42(23) x 10{sup -6} K{sup -1} at 0.4 GPa. Both these unusual phenomena have been linked to increased framework flexibility at high pressure.},
doi = {10.1021/ja073791e},
journal = {J. Am. Chem. Soc.},
number = 33 ; 2007,
volume = 129,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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  • No abstract prepared.