I want to know the structure of BeCl2 in three states (solid, liquid, gas).

BeCl2 is an electron-deprived compound with SP hybridization.

In the solid state, it combines with other BeCl2 molecules to form Be2Cl6.

The formation of an integrated bond between Cl and Be, therefore, achieves greater stability.

Even in the case of gas, it exists as a single molecule.

BCL2 is solid at room temperature. In fact, it can form coordination bonds with other molecules of the same type and form chain structures. BeCl2 is a monomer and, like a polymer, forms chains.

Even after forming a bond with the chlorine atom, it still has 2 empty mouths. It can form 2 coordinate bonds with two chlorine atoms from two adjacent BeCl2 molecules.