According to molecular orbital theory, which of the following will not be a viable molecule?

Options

A. `He_(2)^(2+)`
B. `He^(2+)`
C. `H_(2)^(-)`
D. `H_(2)^(2-)`

Answer

D

Explanation

`{:(He_(2)^(2+),(sigma1s)^(2),B.O.=(2-0)/(2)=1),(He_(2)^(+),(sigma1s)^(2)(sigma^(**)1s)^(1),B.O.=(2-1)/(2)=0.5),(H_(2)^(-),(sigma1s)^(2)(sigma^(**)1s)^(1),B.O.=(2-1)/(2)=0.5),(H_(2)^(2-),(sigma1s)^(2)(sigma^(**)1s)^(2),B.O.=(2-2)/(2)=0):}`
`H_(2)^(2-)` is not viable molecule because bond order is zero.