Messungen an Mo(II)‐, Mo(III)‐,Mo(IV)‐ und Mo(V)‐haltigen sauren wäßrigen Lösungen zeigen, daß die Energie der Absorptionskanten in der Reihe Mo(II) Mo(III) Mo(IV) Mo(V) zunimmt.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTX-ray absorption edge and EXAFS spectroscopic studies of molybdenum ions in aqueous solutionStephen P. Cramer, P. K. Eidem, M. T. Paffett, Jay R. Winkler, Zvi Dori, and Harry B. GrayCite this: J. Am. Chem. Soc. 1983, 105, 4, 799–802Publication Date (Print):February 1, 1983Publication History Published online1 May 2002Published inissue 1 February 1983https://pubs.acs.org/doi/10.1021/ja00342a025https://doi.org/10.1021/ja00342a025research-articleACS PublicationsRequest reuse permissionsArticle Views288Altmetric-Citations56LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Several systems in which molecular hydrogen is produced by photoreduction of protons in aqueous solutions are discussed. One mononuclear system, IrCl2−/3−6, is considered in detail. Ultraviolet irradiation of concentrated HCl solutions of IrCl3−6 yields IrCl2−6 and H2. It is proposed that the reactive excited states are protonated species such as HIrCl2−6 that possess Cl → Ir charge transfer character, and that the photoredox mechanism involves initial release of atomic hydrogen. Irradiation of IrCl2−6 in aqueous HCl solutions over a broad range of wavelengths results in the formation of IrCl3−6 and Cl2. Aqueous HCl is converted to hydrogen and chlorine by coupling the two photoreactions. The possible advantages of using metal cluster complexes to facilitate photochemical hydrogen production are outlined, and related experiments on Mo2X4−8 (X = Cl, Br) and Rh4b6+8 (b = 1,3-diisocyanopropane) are reviewed. Recent experiments have shown that Mo6Cl2−14possesses a long-lived excited state (180 μs in CH3CN; 2eV) that undergoes electron transfer reactions in solutions, and possible extensions of this work aimed at photoreduction of protons are considered.