화학공학소재연구정보센터
Inorganic Chemistry, Vol.34, No.17, 4317-4325, 1995
Analysis of the Absorption and Magnetic Circular-Dichroism Spectra of Low-Spin (S=1/2) Iron(III) Phthalocyanine
Absorption and magnetic circular dichroism (MCD) spectra are reported for metal oxidized bis(cyano)iron(III) phthalocyanine (Na[(CN)(2)Fe(III)Pc(-2)]). Low temperature (<4 K) MCD spectra are used to determine the Lande g factor and the ground state spin and orbital degeneracy in Na[(CN)(2)Fe(III)Pc(-2)]. Analysis of the low temperature, variable field MCD spectra for Na[(CN)(2)Fe(III)Pc(-2)] allow the assignment of the ground state as (2)E(g). Th, orbital degeneracy in the ground state required low temperature absorption and MCD spectra for spectral deconvolution calculations. The fits reported here for Na[(CN)(2)Fe(III)Pc(-2)] represent the first comprehensive spectral analysis of an open shell metallophthalocyanine with an orbitally degenerate ground state, Ring pi-->pi* (Q, B1, B2, N, and L) transitions, e(g)(d pi)-->1b(1u)(pi),1b(2u)(pi) metal to ligand charge transfer (LMCT) transitions, and a series of ligand to metal charge transfer (LMCT) transitions into the 3/4-filled iron(III) e(g)(d pi) orbitals [{a(iu)(pi),b(iu)(pi)}-->e(g)(d pi) (i = 1,2)] are identified in the optical spectra of Na[(CN)(2)Fe(III)Pc(-2)]. Individual electronic transitions (with assignments) are located at 780 (LMCT2); 686 (Q); 645 (LMCT3); 613, 601, 550, and 541 (MLCT1); 513 (LMCT4); 445, 429, 407, and 394 (MLCT2); 346 (B1); 298 (LMCT5); 317 (B2); 273 (N); and 260 nm (L).