\(\mathrm{Be}_{2}\) has an electronic configuration of:

\(\sigma 1 s^{2} \sigma^{*} 1 s^{2} \sigma 2 s^{2} \sigma^{*} 2 s^{2}\)

\(\text { Bond order }=\frac{4-4}{2}=0\)

Thus, Be \(_{2}\) does not exist.