Q. Which one of the following species is diamagnetic in nature?
AIIMSAIIMS 2011
Solution:
A species is said to be diamagnetic if all the electrons present in it are paired.
Species
Electrons
MO Electronic configuration
Magnetic behaviour
$H _{2}$
3
$\sigma 1 s^{2} \overset{*}{\sigma} 1 s^{1}$
Paramagnetic
$H _{2}^+$
1
$\sigma 1 s ^{1}$
Paramagnetic
$H _{2}$
2
$\sigma 1 s ^{2}$
Diamagnetic
$He^{+} _{2}$
3
$\sigma 1s^{2} \overset{*}{\sigma} 1 s^{1}$
Paramagnetic
| Species | Electrons | MO Electronic configuration | Magnetic behaviour |
| $H _{2}$ | 3 | $\sigma 1 s^{2} \overset{*}{\sigma} 1 s^{1}$ | Paramagnetic |
| $H _{2}^+$ | 1 | $\sigma 1 s ^{1}$ | Paramagnetic |
| $H _{2}$ | 2 | $\sigma 1 s ^{2}$ | Diamagnetic |
| $He^{+} _{2}$ | 3 | $\sigma 1s^{2} \overset{*}{\sigma} 1 s^{1}$ | Paramagnetic |