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Chemistry 3150 Transition Metal Chemistry corrections to Part 2 term symbols for d3 Oh. Dr. D.E. Fogg Fall 2002. Electronic spectrum for d 8 Oh. e g. h n. h n. t 2g. 3 T 1g. 3 A 2g. 3 T 1g , 3 T 2g. Recall d 8 is analogous to d 3 ; d 7 is analogous to d 2 . Thus:. 3 A 2g.
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Chemistry 3150 Transition Metal Chemistrycorrections to Part 2term symbols for d3 Oh Dr. D.E. Fogg Fall 2002
Electronic spectrum for d8 Oh eg hn hn t2g 3T1g 3A2g 3T1g, 3T2g Recall d8 is analogous to d3 ; d7 is analogous to d2. Thus: 3A2g 3T1g 3T1g Spin-allowed transitions only shown 3T1g 3T2g 3T2g 3T1g 3A2g D d2, d7 (Oh) d3, d8 (Oh)
Electronic spectra of the tetrahedral anions [VCl4]- (d2) and [VCl4]- (d8) [VCl4]- [VCl4]-: assignments from spectrum 3A23T2 not found 3A23T1 8,900 cm-1 3A23T1 15,000 cm-1 [NiCl4]2- [NiCl4]2-: assignments from spectrum 3T13T2 4,000 cm-1 3T13A2 7,500 cm-1 3T13T1 15,000 cm-1 NB n2 could be to T1, n3 to A2 if D larger! See diagram p. 39 20,000 5,000
How to get Do from electronic spectra (cont’d) • For d2, d7 (Td); d3, d8 (Oh): T1(g) n3 ie d8 Oh Do = n1 T1(g) n2 hn T2(g) n1 A2(g) But for d2, d7 (Oh) and d3, d8 (Td), this simple analysis is complicated by mixing of the T1(g) ground state with the T1(g) excited state, so that n1 is not a “true” measure of Do. A2(g) n3 Do ≠ n1 T1(g) n2 hn T2(g) n1 T1(g)