CHEM 153 - Advanced Inorganic Chemistry PROBLEM SET 3 (due ...

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Part 4: The first example of a trans-dioxo (D 4h ) 3d metal complex was reported in 2007 (J. Am. Chem. Soc. 2007, 129, 12416-12417). Construct an LF diagram (you need only show the 3d levels) for the complex. What is the electronic configuration of the ground state What is the oxo-metal bond order What are the term symbols for the two lowest electronic excited states Did the authors observe transitions from the ground state to these excited states in the absorption spectrum of the complex Should they have Explain briefly. 2. The electronic absorption spectra of [Cr V (N)(CN) 5 ] 3! and [Mn V (N)(CN) 5 ] 3! are shown below. In [Cr V (N)(CN) 5 ] 3! , the 2 B 2 [(xy)] ÷ 2 E[(xz,yz)] absorption band is at 23,300 cm !1 . In [Mn V (N)(CN) 5 ] 3! , the 1 A 1 [(xy) 2 ] ÷ 1 E[(xy)(xz,yz)] absorption band is at 19,400 cm !1 . [Cr(N)(CN) [Cr(N)(CN)5] 5 ] 3 3! [Mn(N)(CN) 5 ] 3! [Mn(N)(CN) 5 ] 3
Use the following orbital splitting diagram to determine the values of ) B in the Cr and Mn complexes. Expressions for the electron-electron repulsion integrals are given below. Assume that B = 500 cm !1 and that C/B = 4. B d 2 : 3 A 2 [(xz,yz) 2 ] E = 2 ) B + A ! 5B 1 A 1 [(xz,yz) 2 ] E = 2 ) B + A + 7B + 4C 1 B 1 [(xz,yz) 2 ] E = 2 ) B + A + B + 2C 1 B 2 [(xz,yz) 2 ] E = 2 ) B + A +B + 2C 1 E[(xy) 1 (xz,yz) 1 ] E = ) B + A + B + 2C 3 E[(xy) 1 (xz,yz) 1 ] E = ) B + A ! 5B 1 A 1 [(xy) 2 ] E = A + 4B + 3C d 3 : 2 E[(xz,yz) 3 ] E = 3 ) B + 3A ! 3B + 4C 4 B 1 [(xy) 1 (xz,yz) 2 ] E = 2 ) B + 3A !15B 2 B 1 [(xy) 1 (xz,yz) 2 ] E = 2 ) B + 3A ! 6B + 3C 2 A 1 [(xy) 1 (xz,yz) 2 ] E = 2 ) B + 3A ! 6B + 3C 2 B 2 [(xy) 1 (xz,yz) 2 ] E = 2 ) B + 3A + 5C 2 A 2 [(xy) 1 (xz,yz) 2 ] E = 2 ) B + 3A ! 6B + 3C 2 E[(xy) 2 (xz,yz) 1 ] E = ) B + 3A ! 3B + 4C 3. Use the foregoing orbital splitting pattern and energy expressions in considering high-spin/low-spin equilibria in tetragonal oxo- and nitrido-metal complexes with d 2 and d 3 configurations. Assume that the excited-state distortion parameter 8 (as defined in the diagrams on the following page) is about 3,400 cm !1 for both high- and low-spin states. a) Find the ) B values at the high-spin/low-spin crossover points for d 2 and d 3 tetragonal oxo- and nitrido-metal complexes. Assume that B = 500 cm !1 and C/B = 4. b) Assume that you have a high-spin/low-spin equilibrium in a d 2 tetragonal oxo- or
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CHEM 153 - Advanced Inorganic Chemistry PROBLEM SET 3 (due ...

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