Transient Absorption Spectrometer

利用所要求的仪器，申请人将表征流体和冷冻溶液、固体和膜中的复合物和分子或其集合的光物理和光化学性质。测量将在可变的温度下进行到77 K，以抑制振动弛豫，几何畸变和热激活表面交叉。这使得能够研究热激活失活途径和自旋状态之间的转变，这将有助于识别发射量子产率的瓶颈（暗态，慢ISC，通过扭曲的表面交叉），并允许研究自旋状态之间的光诱导转变。高光谱分辨率和宽激发和检测范围（UV/维斯/NIR）将被结合起来，以获得激发态景观的完整图片，包括MLCT、自旋翻转和IVCT跃迁的决定性激发态吸收带，这些吸收带通常落入NIR光谱区域。所要求的泵浦探测瞬态吸收光谱仪涵盖了从飞秒到毫秒的广泛时间范围，将用于研究超快激发态动力学，电子和能量转移过程以及光化学生成的中间体的形成及其后续反应。

With the requested instrumentation, the applicants will characterize the photophysical and photochemical properties of complexes and molecules or ensembles thereof in fluid and frozen solutions, solids and films. The measurements will be performed at variable temperatures down to 77 K to suppress vibrational relaxation, geometric distortion and thermally activated surface crossing. This enables the investigation of thermally activated deactivation pathways and transitions between spin states, which shall help to identify bottlenecks for emission quantum yields (dark states, slow ISC, surface crossing via distortion) and allows to study light-induced transitions between spin states. High spectral resolution and broad excitation and detection ranges (UV/Vis/NIR) will be combined to obtain a complete picture of the excited state landscapes, including decisive excited state absorption bands of MLCT, spin-flip and IVCT transitions, which often fall into the NIR spectral region. The requested pump-probe transient absorption spectrometer covers a broad temporal range spanning from femtoseconds to milliseconds, which will be utilized to study the ultrafast excited state dynamics, electron and energy transfer processes as well as the formation of photochemically generated intermediates and their follow-up reactions in all the diverse systems of the applicants.