Phosphorus Dimerization in Gallium Phosphide at High Pressure

Authors

Barbara Lavina, University of Nevada, Las VegasFollow
Eunja Kim, University of Nevada, Las VegasFollow
Hyunchae Cynn, Lawrence Livermore National LaboratoryFollow
Philippe F. Weck, University of Nevada, Las VegasFollow
Kelly Seaborg, University of Nevada, Las VegasFollow
Emily Siska, University of Nevada, Las VegasFollow
Yue Meng, Carnegie Institution of WashingtonFollow
William Evans, Lawrence Livermore National LaboratoryFollow

Document Type

Article

Publication Date

2-9-2018

Publication Title

Inorganic Chemistry

Volume

57

Issue

5

First page number:

2432

Last page number:

2437

Abstract

Using combined experimental and computational approaches, we show that at 43 GPa and 1300 K gallium phosphide adopts the super-Cmcm structure, here indicated with its Pearson notation oS24. First-principles enthalpy calculations demonstrate that this structure is more thermodynamically stable above similar to 20 GPa than previously proposed polymorphs. In contrast to other polymorphs, the oS24 phase shows a strong bonding differentiation and distorted fivefold coordination geometries of both P atoms. The shortest bond of the phase is a single covalent P-P bond measuring 2.171(11) angstrom at synthesis pressure. Phosphorus dimerization in GaP sheds light on the nature of the super-Cmcm phase and provides critical new insights into the high-pressure polymorphism of octet semiconductors. Bond directionality and anisotropy explain the relatively low symmetry of this high-pressure phase.

Keywords

Collaborative access team; Augmented-wave method; Diamond-anvil cell; X-ray-diffraction; Crystal-structure; Black phosphorus; Ab-initio; Group-Iv; Iii-V; Phase

Disciplines

Inorganic Chemistry | Physical Chemistry

Language

English

Repository Citation

Lavina, B., Kim, E., Cynn, H., Weck, P. F., Seaborg, K., Siska, E., Meng, Y., Evans, W. (2018). Phosphorus Dimerization in Gallium Phosphide at High Pressure. Inorganic Chemistry, 57(5), 2432-2437.
http://dx.doi.org/10.1021/acs.inorgchem.7b02478