Photochromic Sodalites: From Natural Minerals to Advanced Applied Materials

Area of Science:

• Materials Science
• Mineralogy
• Solid-State Physics

Background:

• Photochromic natural sodalites, once curiosities, are now recognized for their potential due to advances in artificial synthesis and compositional tuning.
• The photochromism in sodalites arises from photoinduced electron transfer creating color-imparting F-centers.
• Organic photochromes lack the stability of inorganic materials like sodalites.

Purpose of the Study:

• To investigate the mechanism behind sodalite coloration and design artificial photochromic sodalites.
• To explore the potential of synthetic sodalites as alternatives to organic photochromes.
• To develop new experimental and computational techniques for studying solid-state photochromism.

Main Methods:

• Multidisciplinary international collaboration combining geology, material science, spectroscopy, and computational chemistry.
• Experimental and computational characterizations specifically designed for sodalite minerals.
• Quantum chemistry calculations using a multilayer electrostatic embedding methodology.

Main Results:

• Discovery that a mobile sodium atom stabilizes the F-center, explaining the mineral's color and stability.
• Demonstration that synthetic sodalites can be compositionally tuned for a wide range of photochromic properties.
• Proof-of-concept applications developed for UV, X-ray, and gamma-ray detection and sensing, as well as photosensitive films.

Conclusions:

• Synthetic sodalites are a promising platform for inorganic photonics, offering tunable and stable photochromic behavior.
• The understanding of F-center stabilization has led to advancements in experimental (e.g., thermotenebrescence) and computational techniques.
• This research highlights the power of a multidisciplinary approach in unraveling complex material phenomena and driving technological innovation.