25215-76-3Relevant articles and documents
Structure and stability of CN adlayers on Rh(110)
Bondino, Federica,Baraldi, Alessandro,Comelli, Giovanni,Netzer, Falko P.
, p. 31 - 44 (2000)
The formation and stability of CN adlayers on Rh(110), formed by dissociative adsorption of C2N2 at 373 K, have been studied as a function of coverage and temperature by low-energy electron diffraction (LEED), X-ray photoelectron spectroscopy (XPS), and thermal desorption spectroscopy (TDS). Two different CN adsorption states have been distinguished by their different C 1s and N 1s XPS core-level binding energies. The CN-I state is exclusively occupied up to a surface coverage of 0.5 monolayers (ML), where a well-ordered c(2 x 2) LEED pattern is observed. The CN-II state becomes additionally populated at higher coverages from 0.5 ML to the saturation coverage of 0.87 ML. At CN saturation, a c(4 x 2) LEED structure is formed. Desorption of CN as molecular C2N2 occurs only for surface coverages >0.5 ML and appears to be mainly derived from the CN-II state. The onset of C-N bond rupture is indicated at ～450-550 K, depending on the CN coverage; the resulting Nad desorbs at ～580 K from the more crowded surface and in the range of ～650-950 K, whereas Cad remains at the Rh surface and cannot be desorbed thermally.
Polymerisation of cyanogen on graphite and graphite supported copper films
Carley,Chinn,Parkinson
, p. L563-L567 (2002)
The interaction of cyanogen with graphite and graphite supported copper film surfaces was investigated using x-ray photoelectron spectroscopy (XPS). It was found that on both the surfaces an Al Kα x-ray source induced a modification of condensed cyanogen overlayers. The results suggested that modification was x-ray induced polymerization formed via an indirect mechanism involving secondary electrons from the substrate.
Study by static SIMS, XPS and UPS of the adsorption of cyanogen on (100) Ni surfaces
Gouttebaron,Bourgeois,Perdereau
, p. 239 - 246 (2000)
The interaction of cyanogen with (100) Ni surfaces at room temperature was studied using secondary ion mass spectrometry in a static mode, and photoemission spectroscopies (XPS and UPS). It has been shown that cyanogen is adsorbed on this nickel surface in a dissociative mode: atomic carbon and nitrogen are present on the surface as well as CN fragments. These adsorbed species have been characterized by XPS and UPS. Increasing the temperature in the 400 K range increases the rate of the dissociation reaction of CN into atomic carbon and nitrogen. Moreover carbon is found to dissolved into the bulk for temperatures as low as 475 K. No evidence has been found of a polymerized form of cyanogen molecules on this nickel surface, when the temperature is increased unlike the results obtained for the (111) Ni surface.
Vibrational Raman spectroscopic study of cyanogen
Edwards
, p. 37 - 44 (1997)
The vibrational Raman spectra of cyanogen have been obtained in the gas, liquid and solid states. The three Raman active fundamentals, ν1, ν2 and ν4, have been identified in all three phases; whereas the spectra are consistent with D(∞h) molecular symmetry for the gaseous and liquid phases, the solid state spectrum clearly shows the presence of the infrared active and Raman-forbidden ν3 mode. This is possibly indicative of a breakdown of the centro-symmetric structure in the solid state in contradiction of the X-ray diffraction results.
The adsorption and oxidation of cyanogen on copper surfaces
Carley,Chinn,Parkinson
, p. 64 - 74 (2003)
The adsorption of cyanogen on clean and oxygen pre-treated graphite supported copper films, and a polycrystalline copper surface, and the co-adsorption of cyanogen and oxygen on graphite supported copper films, and a polycrystalline copper surface has been studied using X-ray photoelectron spectroscopy. Cyanogen dissociates on the copper surfaces at 300 K, yielding an adsorbed cyano group, CN(a). On the oxygen pre-treated copper surface cyanogen reacts quantitatively with the adsorbed oxygen at 300 K to form a surface cyanate species, NCO. On annealing to 600 K this species decomposes, leaving only N adatoms and residual adsorbed CN on the surface. The co-adsorption of cyanogen and oxygen from a cyanogen-oxygen mixture enhances the formation of NCO to the extent that all available surface oxygen is consumed to form NCO on annealing at 450 K. In the absence of available atomic surface oxygen NCO does not decompose at temperatures up to 600 K. NCO and NCO2 are shown to be the intermediates in the oxidation of cyanogen on copper films and a polycrystalline copper foil.
Penning Ionization of NCCN by Experiment and Theory: A Two-Dimensional Penning lonization Electron Spectroscopic and Quantum Chemical Study
Pasinszki, Tibor,Kishimoto, Naoki,Ogawa, Tetsuji,Ohno, Koichi
, p. 7170 - 7178 (1999)
Dicyanogen, NCCN, is generated for spectroscopic investigations on-line from rubeanic acid, mercury(II) cyanide, and cyanogen iodide and studied in the gas phase by two-dimensional Penning and He I photoelectron spectroscopies, as well as ab initio calculations. From spectroscopic data, the interaction between NCCN and He*(23S) atoms is deduced. The interaction potential for the similarly interacting NCCN-Li(22S) system is obtained from ab initio calculations at the CCSD/6-311++G** level. Experimental and calculated results show that the interaction potential is anisotropic around NCCN, is the most attractive in the nitrogen lone electron pair region, and gradually changes into repulsive as the N-C-He*(or Li) angle opens up to 90°. An unusual collision energy dependences of the partial ionization cross sections are observed, which is interpreted by the unusual interaction potential. For assisting experimental data and studying collision dynamics, classical trajectory calculations are performed for the Penning ionization of the NCCN-He*(23S) system. The spectroscopic investigations predict the existence of thermodynamically stable MLi radicals, and the structure and stability of NCCNLi isomers are calculated at the QCISD/6-311++G** level.
Hexakis(cyanogen)zinc(II) hexafluoridoarsenate - synthesis, structure and a raman speetroscopic study of an octahedral homoleptic cyanogen complex
Beck, Johannes,Zink, Marcus
, p. 687 - 691 (2009)
[Zn(NCCN)6][AsF6]2 (1) was prepared either by dissolving [Zn(SO2)6](Te6)[AsF 6]6 in a SO2/(CN)2 mixture, or by the reaction of [Zn(AsF6/sub
Adsorption geometry of CN on Cu(1 1 1) and Cu(1 1 1)/O
Polcik,Kittel,Hoeft,Terborg,Toomes,Woodruff
, p. 159 - 168 (2004)
The adsorption geometry of CN on Cu(111), both with and without predosing with oxygen, has been investigated using N K-edge near-edge X-ray absorption fine structure (NEXAFS) and C 1s and N 1s scanned-energy mode photoelectron diffraction (PhD). The NEXAFS shows clearly that adsorbed onto clean Cu(111) the C-N axis is closely parallel to the surface, but in the presence of coadsorbed oxygen the average orientation has the axis tilted by 25° away from the surface; this confirms a much earlier report of an oxygen-induced reorientation of CN on this surface based on vibrational spectroscopy. The PhD data show very weak modulations which are rather insensitive to the emission geometry, clearly implying a high degree of disorder or a local adsorption site well-removed from any position of high point group symmetry. The best-fit structure corresponds to the CN lying slightly displaced from the three-fold coordinated hollow sites but with the C and N atoms having single Cu atom nearest neighbours at distances of 1.98±0.05 and 2.00±0.05 A? respectively.
Donor-acceptor complexes of tellurium polycatlonlc clusters with cyanogen
Beck, Johannes,Zink, Marcus
, p. 692 - 699 (2009)
The reactions of cyanogen with Te6[AsF6]4 and Te4[AsF6]2 in SO2 solutions yield Te6[AsF6]4.1.5C2N2 (1) and Te4[A
Molecular orientation of CN adsorbed on Pd(110)
Bondino,Vesselli,Baraldi,Comelli,Verdini,Cossaro,Floreano,Morgante
, p. 10735 - 10740 (2003)
Information on azimuthal molecular orientation as well as on the tilt of the C-N molecular axis on the Pd(110) surface was derived by combining angle-dependent NEXAFS and full-solid-angle PED measurements. NEXAFS data and PED yield independent and consistent conclusions, indicating a nearly parallel CN adsorption on Pd(110), with preferential azimuthal orientation of the C-N molecular axis along the [001] direction. Furthermore, the presence of a 25° tilt of the C-N axis from the surface plane was found with the C atoms closer to the surface than N ones. While the near-parallel bonding geometry of CN found by previous ARUPS data was confirmed, the azimuthal orientation of the bond axis contradicted the conclusions based on the interpretation of photoemission data.
