Department of Physics, University of Strathclyde, SUPA, 107 Rottenrow East, Glasgow, UK.
Inorg Chem. 2010 Oct 18;49(20):9563-73. doi: 10.1021/ic101289s.
Ultrafast transient 2D-IR (T-2D-IR) spectroscopy has been used to study the photolysis products of the [FeFe]hydrogenase enzyme model compound (μ-propanedithiolate)Fe(2)(CO)(6) in heptane solution following irradiation at ultraviolet wavelengths. Observation of coupling patterns between the vibrational modes of the photoproduct species formed alongside examination of the appearance time scales of these signals has uniquely enabled assignment of the photoproduct spectrum to a single pentacarbonyl species. Comparison of the vibrational relaxation rate of the photoproduct with that of the parent is consistent with the formation of a solvent adduct at the vacant coordination site, while anisotropy data in conjunction with density functional theory simulations indicates substitution in an axial rather than equatorial position. No firm evidence of additional short-lived intermediates is seen, indicating that the subsequent chemistry of these species is likely to be strongly defined by the nature of the first solvation shell.
超快瞬态二维红外（T-2D-IR）光谱已被用于研究 [FeFe]氢化酶模型化合物（μ-丙二硫醇盐）Fe(2)(CO)(6)在正庚烷溶液中的光解产物，光解在紫外波长下进行。观察到形成的光产物物种的振动模式之间的耦合模式，同时检查这些信号的出现时间尺度，这独特地将光产物光谱分配给单个五羰基物种。与母体相比，光产物的振动弛豫速率的比较结果一致，表明在空位配位位置形成了溶剂加合物，而各向异性数据结合密度泛函理论模拟表明取代发生在轴向而不是赤道位置。没有看到额外的短寿命中间体的可靠证据，这表明这些物种的后续化学性质很可能强烈取决于第一个溶剂化壳的性质。
