The metallocene bis(cyclopentadienyl)molybdenum(IV) dichloride (Cp2MoCl2; Cp = η5-C5H5) is the first organometallic compound to promote the hydrolysis of phosphonothioates with selective P–S scission in a stoichiometric fashion. This report shows that silver nanoparticles capped with borohydride ions promote turnover in this hydrolytic process, as indicated by 31P NMR studies on the reaction of O,S-diethyl phenylphosphonothioate (DEPP) with Cp2MoCl2 (pH 7). This is the first example of the joint use of nanoparticles and molybdenum metallocenes to promote phosphonothioate hydrolysis. Initial results indicate the turnover may be due to free Ag+(aq) ions present in the solution that arise either from the slow dissolution of the nanoparticles or from interactions with the Ag nanoparticle surface.

Time resolved M2,3-edge XANES spectroscopy of the Co4O4 cubane reveals ultrafast intersystem crossing into a quintet state within 38 fs.

Polystyrene and polyvinyl chloride thin films are explored as sample supports for extreme ultraviolet (XUV) spectroscopy of molecular transition metal complexes. Thin polymer films prepared by slip-coating are flat and smooth, and transmit much more XUV light than silicon nitride windows. Analytes can be directly cast onto the polymer surface or co-deposited within it. The M-edge XANES spectra (40–90 eV) of eight archetypal transition metal complexes (M = Mn, Fe, Co, Ni) are presented to demonstrate the versatility of this method. The films are suitable for pump/probe transient absorption spectroscopy, as shown by the excited-state spectra of Fe(bpy)3 2+ in two different polymer supports.

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We discuss current challenges in the preparation of thin film samples for extreme ultraviolet (XUV) spectroscopy, and offer alternative methods which now enable this spectroscopy to be performed on a wide variety of previously inaccessible compounds. We explored the production, characterization, and use of polymer thin films as highly XUV transmissive sample supports, finding that such thin films could be made via a "slip-coating" technique in which polymer solution is deposited from the shearing meniscus between parallel sliding glass plates. Films made from polystyrene or polyvinyl chloride are thin (10 2 -10 3 nm), homogeneously flat, smooth, and transmit more XUV light than do silicon nitride windows. The analytes of interest are directly cast upon the polymer surface, or codeposited from a common solution. In demonstration of the suitability of these methods towards XUV spectroscopy, we prepared samples of eight different first-row transition metal complexes and report their respective M-edge XANES spectra in the range of 40-90 eV. We additionally report the excited state difference spectrum of Fe(bpy) 3 Cl 2 at 1.5 ps after visible excitation.