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Steric quenching of the switchable mirror effect Phys. Rev. B 75, 104109 (2007)

Troy C. Messina·Casey W. Miller·John T. Markert
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Abstract

Scandium was substituted for yttrium to observe the effect of unit cell size on the optical metal-to-insulator (MIT) transition in the Y_(1-z)Sc_(z)H_(x) alloy system. The optical transmittance decreases significantly for z>0.10. Simultaneous electrical resistivity measurements confirm the transition from trihydride to dihydride behavior with increasing z. These observations imply a quenching of the MIT when the unit cell volume falls below a critical level that is consistent with the boundary between trihydride and non-trihydride forming rare-earth elements. A combinatoric model reveals this formation boundary corresponds to two or more Sc per unit cell.

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Troy C. Messina, Casey W. Miller, John T. Markert. 2007-03-20. Steric quenching of the switchable mirror effect Phys. Rev. B 75, 104109 (2007). https://doi.org/10.1103/physrevb.75.104109

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