StemCET Logo

Chemistry Question 61 – JEE-MAIN 2026

Match the LIST-I with LIST-II List-IList-IIElectronic configuration ofCrystal Field Stabilizationtetrahedral metal ionEnergy (Δt)A. d2I. 0.6B. d4II. 0.8C. d6III. 1.2D. d8IV. 0.4 Choose the correct answer from the options given below:

Recall that in a tetrahedral crystal field, the d-orbitals split into a lower energy 'e' set and a higher energy 't2' set. Also, remember that tetrahedral complexes are almost always high-spin due to the small splitting energy (Δt).

🥷
Ninja StrategySequential Elimination

Verify the match for the first configuration (A) and the last (D) to quickly eliminate most incorrect options, then check one of the remaining configurations to find the answer.

Step 1: Understand d-orbital Splitting in Tetrahedral Fields✦ Active

In a tetrahedral crystal field, the d-orbitals split into two sets: a lower energy doubly degenerate set (e) and a higher energy triply degenerate set (t2). The energy of the e orbitals is 0.6Δt and the energy of the t2 orbitals is +0.4Δt relative to the barycenter. Tetrahedral complexes are high-spin, so electrons fill orbitals singly before pairing.

CFSE=[0.6×(e electrons)+0.4×(t2 electrons)]Δt
Step 2: Calculate CFSE for Each Configuration○ Expand

We calculate the CFSE for each electronic configuration given in List-I:

A. d2: Configuration is e2t20. CFSE = [0.6×2+0.4×0]Δt=1.2Δt.

B. d4: Configuration is e2t22. CFSE = [0.6×2+0.4×2]Δt=[1.2+0.8]Δt=0.4Δt.

C. d6: Configuration is e3t23. CFSE = [0.6×3+0.4×3]Δt=[1.8+1.2]Δt=0.6Δt.

D. d8: Configuration is e4t24. CFSE = [0.6×4+0.4×4]Δt=[2.4+1.6]Δt=0.8Δt.

Step 3: Match the Lists and Select the Correct Option○ Expand

Based on the calculations, we can match the lists:

A (d2) III (1.2) B (d4) IV (0.4) C (d6) I (0.6) D (d8) II (0.8)

The correct combination is A-III, B-IV, C-I, D-II, which corresponds to the third option.

✦ STEM Console utilizes AI models to generate step-by-step explanations and math clues. AI can make mistakes.