Temperature coefficient of electrical resistance of simple liquid metals

The temperature coefficient of electrical resistance has for the first time been numerically determined for $15$ simple liquid metals in view of the third-order term with respect to the pseudopotential of electron-ion interaction. The perturbation theory series for electrical resistance is constructed by the asymptotic expansion method. For all metals, the third-order term turns out to be positive and ranges from several percent to several tens of percent of the second-order term. Its inclusion improves considerably the agreement between the theoretical and experimental values of the temperature coefficient.