14797-71-8Relevant articles and documents
Synchrotron XPS and desorption study of the NO chemistry on a stepped Pt surface
Weststrate,Bakker,Rienks,Vinod,Lizzit,Petaccia,Baraldi,Nieuwenhuys
, p. 1991 - 2001 (2008/10/09)
The interaction of NO with Pt(4 1 0) was studied using high-energy resolution fast XPS and temperature programmed desorption/reaction mass spectroscopy. LEED studies show that the surface in the clean state restructures, which results in the formation of some larger {1 0 0} terraces. STM measurements show, that most terraces are small, ～1 nm. Two different binding energy (BE) components were observed in the N 1s region of the core level spectra, both assigned to molecular forms of NO. NO dissociation starts between 350 and 400 K. This is a significantly higher temperature than previous literature reports suggested. This difference is thought to be caused by the restructuring of the surface used in our experiments. The reaction of NO with H2, NH3 and CO was also studied. The onset of these NO reduction reactions is determined by the NOad dissociation temperature (between 350 and 400 K) and NOad dissociation is the rate limiting step for all the reactions that were studied. Reaction with H2 yields NH3 below 600 K, but the selectivity shifts towards N2 at higher temperatures. We did not find any indication that reaction between NOad and NH3 ad proceeds via a special NO-NH3 intermediate. A new surface species was detected during the reaction between NO and CO, both in the N 1s and the C 1s spectrum. It is tentatively assigned to either CN or CNO. The reactivity of NO on Pt(4 1 0) is compared with the reactivity that was observed for Pt(1 0 0) and other noble metal surfaces, such as Pd and Rh.
Preparation and Vibrational Spectra of 13C and 18O Labelled trans-Dioxotetracyanoosmate(VI), (2-)
Preetz, W.,Sartori, C.
, p. 94 - 98 (2007/10/02)
Through careful acidification of the aqueous solution of (2-) in the presence of CN(-) or (13)CN(-) with acetic acid, (2-) or (2-) are formed, respectively.The reaction of Os(18)O4 and tetrabutylammonium cyanide with glacial acetic acid in anhydrous methanol yields (2-).The shifts of the infrared and Raman bands of the isotopically labelled complexes are in good agreement with Teller-Redlich calculations.The degenerate E modes, expected for tetragonal symmetry, are split by approx. 15 cm-1, indicating an orthorhombic distortion of the complex ion in the solid state.Therefore, all the observed IR- and Raman frequences are assigned according to point group D2h.For the complex containing an (16)O=Os=(18)O axis, the symmetry is lowered to C2v, and the rule of mutual exclusion is restricted.This results in a weak absorption in the infrared spectrum of the Raman active symmetric OsO stretching vibration and vice versa a weak band in the Raman spectrum for the antisymmetric infrared active mode. - Keywords: trans-Dioxotetracyanoosmate(VI), Isotopic Labeling, IR Spectra, Raman Spectra
Transition-state volumes in solvent exchange. Water exchange on the aqueous aquapentaammineruthenium(III) ion
Doine, Hideo,Ishihara, Koji,Krouse, H. Roy,Swaddle, Thomas W.
, p. 3240 - 3242 (2008/10/08)
The rate of water exchange on Ru(NH3)5OH23+ in aqueous CF3SO3H (0.01 mol L-1) is characterized by k298.2 = 2.30 × 10-4 s-1, ΔH* = 91.5 kJ mol-1, ΔS* = -7.7 J K-1 mol-1, and ΔV* = -4.0 cm3 mol-1. The order of lability of M(NH3)5OH23+ in water exchange is (M=) Ru > Cr > Rh > Co ? Ir and is governed by ΔH*. For substitution reactions of metal complexes involving hard leaving groups, the lability sequence first third transition series may be general. For a series of related aqua complexes such as M(NH3)5OH23+, variations in ΔV* for water exchange and the molar volume of the complex as M is changed are largely compensatory, so that the molar volume of the transition state varies relatively little. This reflects reduced accessibility of the complex to associative attack as the central ion becomes smaller.
