In search for a dependence of the density of low-energy excitations (two-level tunneling states, TLS) in amorphous metals on the glass transition temperature Tg or crystallization temperature Tcr, we have performed specific heat measurements on low-Tcr quench-condensed SnxCu1-x (0.54 ≤ x ≤ 0.87) and high-Tcr melt-spun (Mo1-xRux)0.8P0.2 (0.3 ≤ x ≤ 0.7). Both systems are superconducting with Tc>3 K which allows an unambiguous determination of the TLS density of states no from the specific heat for T≪Tc. For all investigated samples, no falls in the range 2 ... 6·1041J-1mol-1 whereas Tcr is at least a factor of 10 higher in the Mo-Ru-P system.

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In-situ specific-heat measurements between 0.3 K and 2 K of quench-condensed amorphous Ge1-xAux films for x = 0.18 and x = 0.14 are reported. These concentrations are close to xc=0.12 for the metal-insulator transition. The samples exhibit bulk superconductivity at 1.6 and 0.6 K respectively, as determined from the discontinuity in the specific heat. The observed strong decrease of the normal-state electronic specific-heat coefficient from x = 0.18 to 0.14 gives evidence that the density of states at the Fermi energy vanishes upon approaching xc, as previously inferred from tunneling measurements.

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