$\ce{XeF4}$ is a well-known square-planar molecule with no dipole moment. Molecules are thus have to be bound to each other by London dispersion forces (LDF) which are known to not be very strong (I think even for large molecules they aren't extremely strong). I was surprised to see that under no...

It is probably an unexplored system, but is there anything known about the low temperature thermodynamic equilibrium state of this? By 'tantalum carbide', I mean $\ce{TaC}$, and by potassium polyselenides, any composition from $\ce{K2Se}$ to pure $\ce{Se}$. Some useful properties include: Equili...