Department of Chemistry, University of California , Berkeley, California 94720, United States.
J Phys Chem B. 2013 Dec 12;117(49):15346-55. doi: 10.1021/jp403791k. Epub 2013 Aug 1.
We demonstrate the capability of temperature-dependent 2D-IR to characterize sources of vibrational population transfer. In a model system of iron diene tricarbonyl "piano stool" complexes, this approach reveals symmetry breaking associated with equilibrium fluctuations and differentiates these from fluxional rearrangement. Tricarbonyl(1,3-butadiene)iron and tricarbonyl(1,5-cyclooctadiene)iron are shown to undergo intramolecular vibrational redistribution (IVR) coupled to the wagging motion of their carbonyl ligands. In the case of both molecules, these equilibrium fluctuations are distinguished from chemical exchange behaviors by their temperature dependence and arguments of molecular symmetry.
我们展示了二维相关红外光谱（2D-IR）随温度变化的能力，以表征振动布居转移的来源。在铁二烯三羰基“钢琴凳”配合物的模型体系中，这种方法揭示了与平衡波动相关的对称性破缺，并将其与通量重排区分开来。三羰基（1,3-丁二烯）铁和三羰基（1,5-环辛二烯）铁被证明经历了与它们的羰基配体的摇摆运动耦合的分子内振动再分配（IVR）。对于这两种分子，这些平衡波动通过其温度依赖性和分子对称性的论证与化学交换行为区分开来。
