Synthesis, Characterization, and Photochemistry of a Dinuclear Cyanide-Bridged Iron(II)-Platinum(IV) Mixed-Valence Compound and Its Implications for the Corresponding Iron(II)-Platinum(IV)-Iron(II) Co
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- 作者：Brian W. Pfennig ; Jenny V. Lockard ; Jamie L. Cohen ; David F. Watson ; Douglas M. Ho ; and Andrew B. Bocarsly
- 刊名：Inorganic Chemistry
- 出版年：1999
- 出版时间：June 14, 1999
- 年：1999
- 卷：38
- 期：12
- 页码：2941 - 2946
- 全文大小：77K
- 年卷期：v.38,no.12(June 14, 1999)
- ISSN：1520-510X
文摘
The mixed-valence compound [(NH3)5PtIV(
-NC)FeII(CN)5]·6H2O was synthesized by the substitution reactionof [PtIV(NH3)5OSO2CF3](OSO2CF3)3 and [FeII(CN)6]4- in aqueous solution and was characterized by UV/vis,IR, and resonance Raman spectroscopies, cyclic voltammetry, and single-crystal X-ray diffractometry. Themonoclinic crystal (space group P21/m (No. 11)) consists of a dinuclear, cyanide-bridged Fe(II)-Pt(IV) moietywith unit cell dimensions of a = 9.3241(5) Å, b = 14.0466(7) Å, c = 9.6938(4) Å, 
= 111.467(2)
, and Z =2. There are also an average of six waters of hydration per unit cell. The R-factors for this structure are R =3.66% and Rw = 7.90%. The electronic spectrum reveals a broad intervalent (IT) charge-transfer absorption atapproximately 420 nm (
= 540 M-1 cm-1). Both the ground-state spectroscopy and the electrochemistry of thiscompound are very similar to those of the corresponding trinuclear adduct [(NC)5FeII(-CN)PtIV(NH3)4(-NC)FeII(CN)5]4-, which has been reported previously. Classical Marcus-Hush theory has been applied in the analysisof the IT band of the dinuclear compound in an effort to elucidate a fuller understanding of the photophysics ofthe trinuclear complex. The data suggest that this latter, centrosymmetric species can be treated theoretically astwo back-to-back dinuclear donor-acceptor (D-A) compounds of the form D-A/A-D, where the Pt(IV) inversioncenter acts as the acceptor for both halves of the molecule. The photochemistry of the dinuclear complex wasalso investigated.
-NC)FeII(CN)5]·6H2O was synthesized by the substitution reactionof [PtIV(NH3)5OSO2CF3](OSO2CF3)3 and [FeII(CN)6]4- in aqueous solution and was characterized by UV/vis,IR, and resonance Raman spectroscopies, cyclic voltammetry, and single-crystal X-ray diffractometry. Themonoclinic crystal (space group P21/m (No. 11)) consists of a dinuclear, cyanide-bridged Fe(II)-Pt(IV) moietywith unit cell dimensions of a = 9.3241(5) Å, b = 14.0466(7) Å, c = 9.6938(4) Å, = 111.467(2), and Z =2. There are also an average of six waters of hydration per unit cell. The R-factors for this structure are R =3.66% and Rw = 7.90%. The electronic spectrum reveals a broad intervalent (IT) charge-transfer absorption atapproximately 420 nm ( = 540 M-1 cm-1). Both the ground-state spectroscopy and the electrochemistry of thiscompound are very similar to those of the corresponding trinuclear adduct [(NC)5FeII(-CN)PtIV(NH3)4(-NC)FeII(CN)5]4-, which has been reported previously. Classical Marcus-Hush theory has been applied in the analysisof the IT band of the dinuclear compound in an effort to elucidate a fuller understanding of the photophysics ofthe trinuclear complex. The data suggest that this latter, centrosymmetric species can be treated theoretically astwo back-to-back dinuclear donor-acceptor (D-A) compounds of the form D-A/A-D, where the Pt(IV) inversioncenter acts as the acceptor for both halves of the molecule. The photochemistry of the dinuclear complex wasalso investigated.