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Calcium Rubidium Nitrate: Mode-Coupling $β$ Scaling without Factorization

M. Goldammer·C. Losert·J. Wuttke·W. Petry·F. Terki·H. Schober·P. Lunkenheimer
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Abstract

The fast dynamics of viscous calcium rubidium nitrate is investigated by depolarized light scattering, neutron scattering and dielectric loss. Fast $β$ relaxation evolves as in calcium potassium nitrate. The dynamic susceptibilities can be described by the asymptotic scaling law of mode-coupling theory with a shape parameter $λ= 0.79$; the temperature dependence of the amplitudes extrapolates to $T_c\simeq 378$ K. However, the frequencies of the minima of the three different spectroscopies never coincide, in conflict with the factorization prediction, indicating that the true asymptotic regime is unreachable.

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M. Goldammer, C. Losert, J. Wuttke, W. Petry, F. Terki, H. Schober, P. Lunkenheimer. 2001-01-29. Calcium Rubidium Nitrate: Mode-Coupling $β$ Scaling without Factorization. https://doi.org/10.1103/physreve.64.021303

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