Chapter 9, Problem 50E

Consider the following electron configuration:

${({\sigma }_{3s})}^2{({\sigma }_{3s}{}^{*})}^2{({\sigma }_{3p})}^2{({\pi }_{3p})}^4{({\pi }_3{{}_p}^{*})}^4$

Give four species that, in theory, would have this electron configuration.