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arXiv · 2509.25887

Kinetics of the photochromic effect in oxygen-containing rare-earth hydrides

Dmitrii Moldarev·Tuan T. Tran·Max Wolff·Daniel Primetzhofer
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Abstract

The kinetics of the photochromic reaction of oxygen-containing rare-earth hydrides is commonly described by an exponential function assuming a single-step process. In this paper, we elaborate on the origin of the photochromic effect in oxygen-containing rare-earth metal hydrides, considering the kinetics of the reaction as a two-step process. We show that the fit to the experimental data is improved drastically when two processes that cause the photodarkening are assumed: a fast reaction rate-limited - for example, electronic or local - process and a slow, e.g. diffusion-limited process.

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Dmitrii Moldarev, Tuan T. Tran, Max Wolff, Daniel Primetzhofer. 2025-09-30. Kinetics of the photochromic effect in oxygen-containing rare-earth hydrides. https://arxiv.org/abs/2509.25887

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