Exploring the structural changes on excitation of a luminescent organic bromine-substituted complex by in-house time-resolved pump-probe diffraction.
Exploring the structural changes on excitation of a luminescent organic bromine-substituted complex by in-house time-resolved pump-probe diffraction.
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DOI：
10.1063/1.4978240
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发表时间：
2017-03
期刊：
影响因子：
--
通讯作者：
Coppens P
中科院分区：
文献类型：
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作者：
Basuroy K;Chen Y;Sarkar S;Benedict J;Coppens P
通过内部单色时间分辨 (TR) 衍射在 90 K 测量了发光二溴苯衍生物 1,4-二溴-2,5-双（辛氧基）苯激发时的结构变化。结果显示，非常短的分子间 Br•••Br 接触距离从 3.290 Å 增加到 3.380 Å。计算表明 Br…Br 相互作用在基态和激发态下都具有强烈的排斥力，但通过激发时接触距离的延长而显着减弱。晶体的稳定性归因于许多弱的C-H·Br和C-H·π分子间相互作用。所描述的研究是内部时间分辨衍射的首次实际应用，它是通过不断提高 X 射线源的亮度和我们探测器的灵敏度而实现的。
The structural changes accompanying the excitation of the luminescent dibromobenzene derivative, 1,4-dibromo-2,5-bis(octyloxy)benzene, have been measured by in-house monochromatic time-resolved (TR) diffraction at 90 K. Results show an increment of the very short intermolecular Br•••Br contact distance from 3.290 Å to 3.380 Å. Calculations show the Br…Br interaction to be strongly repulsive in both the Ground and Excited states but significantly relaxed by the lengthening of the contact distance on excitation. The stability of the crystals is attributed to the many weak C-H···Br and C-H···π intermolecular interactions. The study described is the first practical application of In-House Time-Resolved diffraction, made possible by the continuing increase in the brightness of X-ray sources and the sensitivity of our detectors.