Construction of First Principle Based Adiabatic and Diabatic Hamiltonian for TiO68- unit of BaTiO3 Crystal: Photoemission Spectra and Ferroelectricity

Abstract

The ferroelectric property of BaTiO3 crystal arises from the strong Pseudo Jahn-Teller (PJT) interactions between the non-degenerate ground electronic state, 1A1g and the degenerate 1T1u symmetry states through the nuclear distortions of t1u modes in TiO68- unit. In a d0 electronic configuration of Ti4+ ion, the PJT interaction leads to a stabilization effect, which has been explored using Beyond Born-Oppenheimer (BBO) theory. The 1T1u excited states form a three-state degeneracy, exhibiting feeble Jahn-Teller (JT) distortions over the t2g planes. For the first time, we compute ab initio adiabatic potential energy surfaces (PESs) and non-adiabatic coupling terms (NACTs), and thereafter, diabatic PESs and couplings for the perovskite unit, TiO68-. Using a Time-Dependent Discrete Variable Representation (TDDVR) approach, the theoretical photoemission spectra exhibit good agreement with the experimental ones. Moreover, the experimental observation on order parameter associated with ferroelectric properties of BaTiO3 crystal show close resemblance with present and other theoretical predictions.

Supplementary files

Transparent peer review

To support increased transparency, we offer authors the option to publish the peer review history alongside their article.

View this article’s peer review history

Article information

Article type
Paper
Submitted
10 May 2025
Accepted
15 Jun 2025
First published
16 Jun 2025

Phys. Chem. Chem. Phys., 2025, Accepted Manuscript

Construction of First Principle Based Adiabatic and Diabatic Hamiltonian for TiO68- unit of BaTiO3 Crystal: Photoemission Spectra and Ferroelectricity

M. K. Sah, S. Mukherjee, S. Adhikari and S. Ravi, Phys. Chem. Chem. Phys., 2025, Accepted Manuscript , DOI: 10.1039/D5CP01761K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements