ELECTRIC AND MOLECULAR STRUCTURE INVESTIGATION

去年的进展报告，我们研究了溶剂对 通过对吲哚团簇的研究，得到了吲哚的一个光谱 被一个未被认识到的技术问题所破坏。 结果 得到，284 nm吲哚带依次转移到 通过连续加入1 - 13个正己烷分子的红色是正确的。 然而，己烷分子的观察是正确的。 然而 观察到光谱带比预期的要宽 促使我们重新审视我们的工作 我们发现， 在我们的大多数研究中使用的载气，Ar，紧密结合到 吲哚或团簇并扰乱了光谱。 当 用He作为载气重复实验， 获得了窄的光谱带，但不可能达到 大的集群规模。 我们还调查了 提出了吲哚氢键光谱移动的机制 在溶液中的发色团，其中H-供体和 在气相中，氢受体是必需的， 仅推断出H-供体的结合是必需的。 我们的研究结果表明 结合H-供体是产生光谱位移所必需的， H-受体首先结合，然后保持牢固结合。

Last year's progress report on our studied of solvent effects on the spectra of indole through an investigation of indole clusters was found to be marred by an unrecognized technical problem. The results obtained, that the 284 nm indole band was shifted successively to the red by the successive addition of 1 - 13 n-hexane molecules is correct. However the observation that the hexane molecules is correct. However the observation that the spectral bands were broader than expected caused us to reexamine our work. We found that one molecule of the carrier gas used in most of our investigations, Ar, bound tightly to either indole or the cluster and perturbed the spectrum. When the experiments were repeated with He as the carrier gas the anticipated narrow spectral bands were obtained but it was not possible to attain large cluster sizes. We also investigated the discrepancy between the mechanism proposed for the hydrogen-binding spectral shift of the indole chromophore in solution, where the binding of both of H-donor and a H-acceptor was deduced to be necessary, and in the gas phase, where the only binding of the H-donor was deduced necessary. Our results indicate that binding the H-donor is necessary to produce the spectral shift but the H-acceptor binds first and remains firmly bound thereafter.