Phase stabilities at a glance: Stability diagrams of nickel dipnictides
Abstract
In the course of the recent advances in chemical structure prediction, a straightforward type of diagram to evaluate phase stabilities is presented based on an expedient example. Crystal structures and energetic stabilities of dipnictides NiPn{sub 2} (Pn = N, P, As, Sb, Bi) are systematically investigated by first principles calculations within the framework of density functional theory using the generalized gradient approximation to treat exchange and correlation. These dipnictides show remarkable polymorphism that is not yet understood systematically and offers room for the discovery of new phases. Relationships between the concerned structures including the marcasite, the pyrite, the arsenopyrite/CoSb{sub 2}, and the NiAs{sub 2} types are highlighted by means of common structural fragments. Electronic stabilities of experimentally known and related AB{sub 2} structure types are presented graphically in socalled stability diagrams. Additionally, competing binary phases are taken into consideration in the diagrams to evaluate the stabilities of the title compounds with respect to decomposition. The main purpose of the stability diagrams is the introduction of an image that enables the estimation of phase stabilities at a single glance. Beyond that, some of the energetically favored structure types can be identified as potential new phases.
 Authors:
 University of Regensburg, Institute of Inorganic Chemistry, Universitätsstr. 31, 93040 Regensburg (Germany)
 (New Zealand)
 School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland (New Zealand)
 Publication Date:
 OSTI Identifier:
 22251295
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 139; Journal Issue: 21; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CRYSTAL STRUCTURE; DECOMPOSITION; DENSITY FUNCTIONAL METHOD; DIAGRAMS; MARCASITE; NICKEL; PHASE STABILITY; PYRITE
Citation Formats
Bachhuber, F., School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, Rothballer, J., Weihrich, R., Email: richard.weihrich@chemie.unir.de, Söhnel, T., and Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University Auckland, Auckland. Phase stabilities at a glance: Stability diagrams of nickel dipnictides. United States: N. p., 2013.
Web. doi:10.1063/1.4832698.
Bachhuber, F., School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, Rothballer, J., Weihrich, R., Email: richard.weihrich@chemie.unir.de, Söhnel, T., & Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University Auckland, Auckland. Phase stabilities at a glance: Stability diagrams of nickel dipnictides. United States. doi:10.1063/1.4832698.
Bachhuber, F., School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland, Rothballer, J., Weihrich, R., Email: richard.weihrich@chemie.unir.de, Söhnel, T., and Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University Auckland, Auckland. 2013.
"Phase stabilities at a glance: Stability diagrams of nickel dipnictides". United States.
doi:10.1063/1.4832698.
@article{osti_22251295,
title = {Phase stabilities at a glance: Stability diagrams of nickel dipnictides},
author = {Bachhuber, F. and School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland and Rothballer, J. and Weihrich, R., Email: richard.weihrich@chemie.unir.de and Söhnel, T. and Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study, Massey University Auckland, Auckland},
abstractNote = {In the course of the recent advances in chemical structure prediction, a straightforward type of diagram to evaluate phase stabilities is presented based on an expedient example. Crystal structures and energetic stabilities of dipnictides NiPn{sub 2} (Pn = N, P, As, Sb, Bi) are systematically investigated by first principles calculations within the framework of density functional theory using the generalized gradient approximation to treat exchange and correlation. These dipnictides show remarkable polymorphism that is not yet understood systematically and offers room for the discovery of new phases. Relationships between the concerned structures including the marcasite, the pyrite, the arsenopyrite/CoSb{sub 2}, and the NiAs{sub 2} types are highlighted by means of common structural fragments. Electronic stabilities of experimentally known and related AB{sub 2} structure types are presented graphically in socalled stability diagrams. Additionally, competing binary phases are taken into consideration in the diagrams to evaluate the stabilities of the title compounds with respect to decomposition. The main purpose of the stability diagrams is the introduction of an image that enables the estimation of phase stabilities at a single glance. Beyond that, some of the energetically favored structure types can be identified as potential new phases.},
doi = {10.1063/1.4832698},
journal = {Journal of Chemical Physics},
number = 21,
volume = 139,
place = {United States},
year = 2013,
month =
}

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