$$(\sigma_{1s})^{2} (\sigma_{1s}^{*})^{2} (\sigma_{2s})^{2} (\sigma_{2s}^{*})^{2} (\pi_{2p})^{4} $$

$$(\sigma_{1s})^{2} (\sigma_{1s}^{*})^{2} (\sigma_{2s})^{2} (\sigma_{2s}^{*})^{2} (\pi_{2p})^{4}(\sigma_{2p})^{2} $$

$$(\sigma_{1s})^{2} (\sigma_{1s}^{*})^{2} (\sigma_{2s})^{2} (\sigma_{2s}^{*})^{2} (\pi_{2p})^{4}(\sigma_{2p})^{2} (\sigma_{2p}^{*})^{2}$$

$$(\sigma_{1s})^{2} (\sigma_{1s}^{*})^{2} (\sigma_{2s})^{2} (\sigma_{2s}^{*})^{2} (\sigma_{2p})^{2}(\pi_{2p})^{4}$$