Question

Draw the structure of:

A $BeC{l}_2$ (vapour)

B $BeC{l}_2$ (solid)

Answer 1

$\text{Structure of}BeC{l}_2\text{in vapour phase}:$

In the vapour phase $BeC{l}_2$ forms a chloro-bridged dimer which dissociates into the linear monomer at high temperatures of the order of $1200K$.

Dimer and monomer structure of $BeC{l}_2$ shown below
$\text{Structure of}BeC{l}_2\text{in solid phase}:$

In solid state, Beryllium chloride forms a polymer structure. In excited state beryllium has two half-filled orbitals by the help of these orbitals it forms two covalent bonds with two chlorine atoms.

After it, to complete its octet it forms two coordinate bonds with two neighbouring chlorine atoms by the help of two empty orbitals.
This leads to formation of $B{e}_{2}C{l}_6$, which has a tetrahedral geometry. By the repeating of these unit, we get a polymeric structure.

Polymeric structure of $BeC{l}_2$ shown below