Q2(b)(ii). Two bands in high-spin [CoF₆]³⁻
Discuss the following observation: (ii) The electronic spectrum of [CoF₆]³⁻ contains two bands with maxima at 11500 cm⁻¹ and 14500 cm⁻¹.
Answer in brief
The two bands arise from Jahn–Teller splitting of the excited ⁵Eg state of high-spin d⁶ Co³⁺.
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Covers[CoF6]3- spectrumexcited-state Jahn-Tellerhigh-spin d6d-d transitionsband splitting
All parts of Question 2
- 2(a)(i) Fluorite and antifluorite5 marks
- 2(a)(ii) Schottky and Frenkel defects5 marks
- 2(a)(iii) Normal and inverse spinels5 marks
- 2(b)(i) Regular and flattened tetrahedra5 marks
- 2(b)(ii) Two bands in high-spin [CoF₆]³⁻5 marks
- 2(c) Polymorphism in crystals5 marks