Is there any pair of substance which has a negative surface tension?

Question

I assume that positive surface tension for the interface between two substance implies that the molecules at the boundary are more "comfortable" - their energy is lower when surrounded by similar atoms/molecules ( giving rise to cohesive force ) rather than when they are surrounded by dissimilar atoms/molecules( giving rise to adhesive force ).
Is there any solid-liquid pair for which the adhesive force is more stabilizing than the cohesive force?

Cort Ammon · Answer

In such a case, the materials will rapidly merge into one homogenous mass.  The term you are looking for is "miscible."  Any two miscible materials are more stable in a distributed arrangement than they would be in a separated arrangement.
Adrian Howard points out a classic example in the comments: alcohol and water.  If the two are combined in the same container, they will mix until evenly distributed, no matter how much of either one you bring to the mix.

Is there any pair of substance which has a negative surface tension?

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