Specific-heat exponent and critical-amplitude ratio at the Lifshitz multicritical point

The specific-heat critical exponent, ${\alpha }_L$, associated with the uniaxial Ising-type Lifshitz point (LP) in MnP, was determined experimentally from the study of the magnetic susceptibility, χ, perpendicular to the easy axis, as a function of the magnetic field. According to generalized scaling theory, the divergence of χ, at the ferromagnetic-paramagnetic phase boundary, near the LP, is governed by α. We found ${\alpha }_L$ between 0.4 and 0.5, in agreement with estimates from other experimentally known critical exponents in MnP. For the critical-amplitude ratio we found $A^{+}$/$A^{\mathrm{-}}$=0.65±0.05. .AE