Abstract
Using the van der Waals density functional with C09 exchange (vdW-DF-C09), which has been applied to describing a wide range of dispersion-bound systems, we explore the physical properties of prototypical ABO3 bulk ferroelectric oxides. Surprisingly, vdW-DF-C09 provides a superior description of experimental values for lattice constants, polarization and bulk moduli, exhibiting similar accuracy to the modified Perdew-Burke-Erzenhoff functional which was designed specifically for bulk solids (PBEsol). The relative performance of vdW-DF-C09 is strongly linked to the form of the exchange enhancement factor which, like PBEsol, tends to behave like the gradient expansion approximation for small reduced gradients. These results suggest the general-purpose nature of the class of vdW-DF functionals, with particular consequences for predicting material functionality across dense and sparse matter regimes.
Original language | English |
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Article number | 43482 |
Journal | Scientific Reports |
Volume | 7 |
DOIs | |
State | Published - Mar 3 2017 |
Funding
S.F.Y., M.E., and V.R.C. are supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division and the Office of Science Early Career Research Program. K.C.P. and S.M.N. are supported by the National Science Foundation (DMR 1309114). K.C.P. also acknowledges the internship through the Advanced Short Term Research Opportunity (ASTRO) program at Oak Ridge National Laboratory (ORNL), supported by the U.S. DOE, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division and the Office of Science Early Career Research Program. Y.W.L. is sponsored by the U.S. DOE, Office of Advanced Scientific Computing Research. We gratefully acknowledge the computational resources provided by the National Energy Research Scientific Computing Center (NERSC), which is supported by the Office of Science of the U.S. DOE under Contract No. DE-AC02-05CH11231 and the Oak Ridge Leadership Computing Facility (OLCF), which is supported by the Office of Science of the U.S. DOE under Contract No. DE-AC05-00OR22725.