Paper: CSIR-NET December 2011 · Subject: Physical Chemistry · Chapter: Group Theory · Topic: Symmetry Elements Point Groups · Marks: 2 · Difficulty: Medium
The pair of symmetry point groups that are associated with only polar molecules is
(a)$\mathrm{C_{2v}}, \mathrm{D_{Bh}}$
(b)$\mathrm{C_{3v}}, \mathrm{C_{2h}}$
(c)$\mathrm{D_{2h}}, \mathrm{T_d}$
(d)$\mathrm{C_{2v}}, \mathrm{C_{Bv}}$
Answer
Answer: D ✓ checked by 4AB · confidence high
Explanation
Only groups C_n, C_nv and C_s allow a permanent dipole; C₂v and C∞v both do, whereas C₂h, D₂h, D∞h and T_d do not.