# Can a solid and liquid be miscible?

To be specific, what I mean is: is the following situation possible? At given temperature T, there are two substances, X and Y, such that pure X is a solid, pure Y is a liquid, and X and Y mix to form a single phase in all proportions.

The closest I could find was this phase diagram for silver and gold (two very similar metals, I suppose): http://www.crct.polymtl.ca/fact/phase_diagram.php?file=Ag-Au.jpg&dir=SGTE

But it looks like there is still a narrow region in which there are two phases.

• theoretically speaking, a polymeric compound on itself is solid (well, kind of), but some polymers can dissolve in chosen solvents, providing full spectrum from (kind of) solid trough viscous liquid to normal liquid. Good luck finding concrete example with more traditional chemistry. Aug 24 '14 at 8:28

These materials are being investigated as hydrogen storage materials, so essentially the hydrogen molecules interact with the metal to form hydrides, "$\ce{H-}$", which recombine under different conditions to reform $\ce{H2}$ as required. A review of this technique is given here.