Q70 · CSIR-NET Chemistry, December 2017

Paper: CSIR-NET December 2017 · Subject: Physical Chemistry · Chapter: Group Theory · Topic: Group Theory – General · Marks: 2 · Difficulty: Easy

The $\mathrm{b}_{1 \mathrm{u} \rightarrow \mathrm{b} 2 \mathrm{g} \text { transition in ethylene is (Use Table 1) }}$
(a)not allowed
(b)allowed by to x-polarized light
(c)allowed by y-polarized light
(d)allowed by z-polarized light
Answer
Answer: D ✓ checked by 4AB · confidence high
Explanation
b₁u × b₂g = b₃u, which transforms like z in D₂h. The transition is allowed with z-polarised light (d).

Study loop for Group Theory

1. Practise the PYQsPrevious-year questions, with answers

· Browse this chapter in the app