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Universal scaling of latent heat of orbital order-disorder transition with average R-site ion size in perovskite RMnO3 systems

Parthasarathi Mondal·Dipten Bhattacharya
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Abstract

The latent heat (L) of orbital order-disorder transition in single-valent perovskite manganite series La(1-x)R(x)MnO3 (R = Pr, Nd, Gd; x = 0.0-1.0) decreases with the decrease in average R-site radius following a universal scaling law L. ^2/sigma^2 ~ exp ( ), where sigma^2 is the variance in R-site radius, and eventually reaches zero at a critical R-site radius _c ~ 1.180 Angstrom. Such a drop in L is due, possibly, to a universal pattern of evolution of finer orbital domain structure with the drop in as well as with the increase in sigma^2 irrespective of R-site ion type.

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Parthasarathi Mondal, Dipten Bhattacharya. 2006-08-03. Universal scaling of latent heat of orbital order-disorder transition with average R-site ion size in perovskite RMnO3 systems. https://arxiv.org/abs/cond-mat/0608080

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