24646-85-3Relevant academic research and scientific papers
Cavity ring-down laser absorption spectroscopy of the E3Δ- X3Δ transition of VN
Ma, Tongmei,Leung,Cheung
, p. 5333 - 5337 (2004)
The (0,0) band of the electronic transition of VN near 450.5 nm has been investigated using the technique of laser vaporization/reaction with free jet expansion and cavity ring-down laser absorption spectroscopy. A new transition system was observed, which has been assigned as the E3Δ-X 3Δ system. All three ΔΩ = 0 subband transitions were recorded and rotationally analyzed. A least-squares fit of the measured line positions yielded molecular constants for the new E3Δ state. The bond length, ro, of the E3Δ state was determined to be 1.6937 A, which is the longest among the known states of VN. The E3Δ state is expected to arise from the electronic configuration 1δ110σ1, where the 10σ orbital is an antibonding orbital. A comparison of the observed electronic states of VN to those of the isoelectronic TiO molecule supports the assignment.
Rotational fine, and hyperfine analyses of the (0,0) band of the D 3Π-X 3Δ system of vanadium mononitride
Balfour, Walter J.,Merer, Anthony J.,Niki, Hideaki,Simard, Benoit,Hackett, Peter A.
, p. 3288 - 3303 (1993)
The VN molecule has been produced in a molecular beam apparatus using a laser vaporization source and its D 3Π-X 3Δ(0,0) band has been studied by laser-induced fluorescence at low (ca. 0.1 cm-1) and sub-Doppler resolution (ca. 0.004 cm-1).Lifetimes of single rotational levels of the D 3Π0 component have been measured and interpreted.Rotational, fine, and hyperfine structures is six of the nine subbands possible for a 3Π 3Δ transition have been recorded.Both states exhibit a rapid transition from case (a) -> case (b) coupling cases, manifestedby reversals in the Lande patterns of the hyperfine structure.The data have been reduced to a set of 35 molecular constants using a modified case (aβ) effective Hamiltonian in which two additional magnetic hyperfine parameters are required for each state.The distortions in the hyperfine structure are due almost entirely to second-order spin-orbit interaction between states arising from the same configuration.Analysis of the derived parameters indicates that the X 3Δ state is well represented by the single electron configuration ...8?2 3?4 9?1 1δ1, in which the 9? molecular orbital (MO) is a V 4s-4p hybrid (88percent V 4s) and the 1δ MO is a pure V 3d orbital; the dominant configuration for the D 3Π state is ...8?2 3?4 1δ1 4?1, in which the 4? MO is an antibonding orbital composed of at most 82percent V 3d?.The isoconfigurational a 1Δ and e 1Π states are calculated to lie 3390 and 2200 cm-1 above their respective high spin companions.The lambda doubling in the D 3Π0 component has been interpreted in terms of spin-orbit interactions with the B 3Σ- and d 1Σ+ states, both states arisingfrom the ... 8?2 3?4 1δ2 configuration; the d 1Σ+ state is known to lie 102 cm-1 above D 3Π0, while the B 3Σ- state probably lies about 8000 cm-1 below.
The permanent electric dipole moments of chromium and vanadium mononitride: CrN and VN
Steimle, Timothy C.,Robinson, J. Scott,Goodridge, Damian
, p. 881 - 889 (2007/10/03)
The Pe(1), F = 2.5 branch feature of the (0,0) D 3Π0e - X 3Δ1 band system of 51 VN was recorded as a function of an applied static electric field. The resultant Stark splitting and shifts were analyzed giving values of 3.07(7) D and 6.1(4) D for the X 3Δ1 and D 3Π0e states, respectively, for the magnitude of the permanent electric dipole moment, μ. Similarly, the Ree(0.5) branch feature of the (0,0) A 4Π3/2 - X 4Σ- band system of 52 CrN was recorded as a function of an applied static electric field and analyzed to produce μ values of 2.31(4) D and 5.42(2) D for the X 4Σ- and A 4Π3/2 states, respectively. In order to facilitate the dipole moment determinations for 52CrN it was necessary to record and analyze the field free spectrum of the (0,0) A 4Π3/2 - X 4Σ- subband system. A comparison of the dipole moments for the first row monoxides and mononitrides is made and trends are discussed with reference to a molecular orbital correlation scheme.
Gas-Phase Chemistry of Transition Metal-Imido and -Nitrene Ion Complexes. Oxidative Addition of N-H Bonds in NH3 and Transfer of NH from a Metal Center to an Alkene
Buckner, Steven W.,Gord, James R.,Freiser Ben S.
, p. 6606 - 6612 (2007/10/02)
We report here on the gas-phase chemistry of a number of bare transition metal-nitrene and -imido ion complexes, MNH+.Group 3, 4, and 5 atomic metal ions react with NH3 at thermal energies to generate MNH+ via dehydrogenation.A reaction mechanism is proposed involving initial oxidative addition to an N-H bond, in analogy to mechanisms proposed for reactions of gaseous atomic metal ions with hydrocarbons.Cr+ reacts with NH3 via slow condensation to form CrNH3+, as do all group 6-11 atomic metal ions investigated.However, excited-state Cr+ reacts with NH3 via bond-insertion reactions to form CrNH2+ and CrNH+.An unidentified metastable electronic state of Cr+, produced by direct laser desorption of chromium foil, reats with much higher efficiency than does kinetically excited Cr+.FeO+ reacts with NH3 to generate FeNH+ with loss of H2O.Thermochemical studies of VNH+ and FeNH+ involving ion-molecule reactions indicate values of D0(V+-NH) = 101 +/- 7 kcal/mol and D0(Fe+-NH) = 54 +/- 14 kcal/mol, the latter value in accord with D0(Fe+-NH) = 61 +/- 5 kcal/mol obtained from photodissociation.The high bond strength for VNH+ indicates multiple bonding, analogous to that in the isoelectronic VO+, while the weaker bond strength for FeNH+ indicates a single bond, analogous to that in the isoelectronic FeO+.Proton-transfer experiments indicate PA(VN) = 220 +/- 4 kcal/mol from which ΔHf(VN) = 111 +/- 9 kcal/mol and D0(V-N) = 125 +/- 9 kcal/mol are obtained.VNH+ is unreactive with ethene and benzene, but FeNH+ transfers NH to ethene and benzene through metathesis and homologation reactions.A cyclic metalloaminobutane intermediate is consistent with the products of the FeNH+/ethene reaction.
