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Title: Symmetry-adapted order parameters and free energies for solids undergoing order-disorder phase transitions

Authors:
; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1402115
Grant/Contract Number:
SC0008637; AC02-05CH1123
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 96; Journal Issue: 13; Related Information: CHORUS Timestamp: 2017-10-23 12:25:18; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Natarajan, Anirudh Raju, Thomas, John C., Puchala, Brian, and Van der Ven, Anton. Symmetry-adapted order parameters and free energies for solids undergoing order-disorder phase transitions. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.96.134204.
Natarajan, Anirudh Raju, Thomas, John C., Puchala, Brian, & Van der Ven, Anton. Symmetry-adapted order parameters and free energies for solids undergoing order-disorder phase transitions. United States. doi:10.1103/PhysRevB.96.134204.
Natarajan, Anirudh Raju, Thomas, John C., Puchala, Brian, and Van der Ven, Anton. 2017. "Symmetry-adapted order parameters and free energies for solids undergoing order-disorder phase transitions". United States. doi:10.1103/PhysRevB.96.134204.
@article{osti_1402115,
title = {Symmetry-adapted order parameters and free energies for solids undergoing order-disorder phase transitions},
author = {Natarajan, Anirudh Raju and Thomas, John C. and Puchala, Brian and Van der Ven, Anton},
abstractNote = {},
doi = {10.1103/PhysRevB.96.134204},
journal = {Physical Review B},
number = 13,
volume = 96,
place = {United States},
year = 2017,
month =
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on October 23, 2018
Publisher's Accepted Manuscript

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  • Non-covalent interactions occur between and within all molecules and have a profound impact on structural and electronic phenomena in chemistry, biology, and material science. Understanding the nature of inter- and intramolecular interactions is essential not only for establishing the relation between structure and properties, but also for facilitating the rational design of molecules with targeted properties. These objectives have motivated the development of theoretical schemes decomposing intermolecular interactions into physically meaningful terms. Among the various existing energy decomposition schemes, Symmetry-Adapted Perturbation Theory (SAPT) is one of the most successful as it naturally decomposes the interaction energy into physical and intuitivemore » terms. Unfortunately, analogous approaches for intramolecular energies are theoretically highly challenging and virtually nonexistent. Here, we introduce a zeroth-order wavefunction and energy, which represent the first step toward the development of an intramolecular variant of the SAPT formalism. The proposed energy expression is based on the Chemical Hamiltonian Approach (CHA), which relies upon an asymmetric interpretation of the electronic integrals. The orbitals are optimized with a non-hermitian Fock matrix based on two variants: one using orbitals strictly localized on individual fragments and the other using canonical (delocalized) orbitals. The zeroth-order wavefunction and energy expression are validated on a series of prototypical systems. The computed intramolecular interaction energies demonstrate that our approach combining the CHA with strictly localized orbitals achieves reasonable interaction energies and basis set dependence in addition to producing intuitive energy trends. Our zeroth-order wavefunction is the primary step fundamental to the derivation of any perturbation theory correction, which has the potential to truly transform our understanding and quantification of non-bonded intramolecular interactions.« less
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