English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We revisit the well-known Mollwo-Ivey relation that describes the "universal"dependence of the absorption energies of F-type color centers on the latticeconstant $a$ of the alkali-halide crystals, $E_{\mbox{abs}}\propto a^{-n}.$ Weperform both state-of-the-art ab-initio Quantum Chemistry and post-DFTcalculations of F-center absorption spectra. By "tuning" independently thelattice constant and the atomic species we show that the scaling of the latticeconstant alone (keeping the elements fixed) would yield $n=2$ in agreement withthe "particle-in-the-box" model. Keeping the lattice constant fixed andchanging the atomic species enables us to quantify the ion-size effects whichare shown to be responsible for the exponent $n \approx 1.8$.

Ab-initio perspective on the Mollwo-Ivey relation for F-centers in alkali halides