Q. Which one of the following species is diamagnetic in nature ?
AIEEEAIEEE 2005Chemical Bonding and Molecular Structure
Solution:
A species is said to be diamagnetic if it has all electrons paired.
Species Electrons MO
Electronic
configuration Magnetic
behaviour $H^-_2$ 3 $\sigma1s^{2}\,\sigma^{\circ}\,1s^{1}$ Paramagnetic $H^+_2$ 1 $\sigma1s^{1}$ Paramagnetic $H_2$ 2 $\sigma1s^{2}$ Diamagnetic $He^+_2$ 3 $\sigma1s^{2}\,\sigma^{\circ}\,1s^{1}$ Paramagnetic
| Species | Electrons | MO Electronic configuration | Magnetic behaviour |
|---|---|---|---|
| $H^-_2$ | 3 | $\sigma1s^{2}\,\sigma^{\circ}\,1s^{1}$ | Paramagnetic |
| $H^+_2$ | 1 | $\sigma1s^{1}$ | Paramagnetic |
| $H_2$ | 2 | $\sigma1s^{2}$ | Diamagnetic |
| $He^+_2$ | 3 | $\sigma1s^{2}\,\sigma^{\circ}\,1s^{1}$ | Paramagnetic |