# Mechanisms of localization in isotope-substituted dynamical Jahn-Teller systems

## TL;DR

This paper investigates how isotope substitution affects the localization mechanisms of Jahn-Teller deformations and vibronic wavefunctions, revealing potential and kinetic localization regimes depending on vibronic coupling strength.

## Contribution

It provides a detailed analysis of localization mechanisms in isotope-substituted dynamical Jahn-Teller systems, highlighting the role of vibronic coupling strength.

## Key findings

- Localization in the potential trough occurs at strong vibronic coupling.
- Localization becomes kinetic type at intermediate and weak coupling.
- Vibronic levels remain double degenerate regardless of isotope substitution.

## Abstract

The mechanisms of localization of Jahn-Teller deformations and vibronic wavefunctions in isotope substituted dynamical Jahn-Teller systems are elucidated. It is found that the localization in the trough is of potential type in the case of strong vibronic coupling, while it becomes of kinetic type in the case of intermediate and weak coupling. It is shown that the vibronic levels in the linear $E\otimes e$-problem remain double degenerate upon arbitrary isotope substitution on the reasons similar to time reversal symmetry in which the role of spin is played by orbital pseudospin.