We present the data of the point contact (PC) Andreev-reflection measurements on the new paramagnetic superconductor Mo3Sb7, which were used for finding the energy gap Δ and upper critical field Hc 2 for this compound. The maximum gap value, reduced to the zero temperature via the Bardeen–Cooper–Schrieffer (BCS) theory, turned out to be  meV, which is slightly smaller than that expected from the BCS theory,  meV. The temperature dependence of the gap obeys the BCS theory approximately. The Hc 2(0) value of about 16.5 kOe was obtained from fitting the experimental data to the conventional H(T) dependence, which is quadratic in temperature. This value is in close agreement with the result from magnetization measurements of 17.2 kOe.

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Point-contact (PC) Andreev-reflection experiments on the new paramagnetic superconductor Mo3Sb7 are reported for which we have observed strong distinctions in the PC spectra measured for different contact axis orientations. Analysis of the PC spectra in the framework of the Blonder–Tinkham–Klapwijk theory has shown that the gap parameter Δ is strongly anisotropic, varying over a very wide range depending on the contact orientation: the maximum Δmax can exceed the minimum Δmin by at least 40 times. For these and other reasons we suggest that Mo3Sb7 is not a trivial BCS (s-wave) superconductor but rather has (s+g)-wave or another unconventional pairing symmetry.