It has been shown that the observed correlation between the resistivity ρ of high-resistive metallic alloys and the sign of the temperature derivative dρ/dT can be explained by taking into account the weak localization. This correlation is known as Mooij rule: the derivative dρ/dT is negative for alloys with resistivity in the range of 300÷150μΩ⋅cm, which corresponds to the electron mean free path about the interatomic distance; however, this derivative is positive for alloys with lower resistivity.
Cite
@article{arxiv.1112.0429,
title = {Mooij Rule and Weak Localization},
author = {V. F. Gantmakher},
journal= {arXiv preprint arXiv:1112.0429},
year = {2011}
}