7789-25-5Relevant articles and documents
A quantum mechanical, time-dependent wave packet interpretation of the diffuse structures in the S0 --> S1 absorption spectrum of FNO: Coexistence of direct and indirect dissociation
Suter, Hans Ulrich,Huber, J. Robert,Dirke, Michael von,Untch, Agathe,Schinke, Reinhard
, p. 6727 - 6734 (1992)
We have investigated the photodissociation of FNO in the first absorption band (S0 --> S1) by a two-dimensional wave packet study based on an ab initio potential energy surface.The quantum chemical calculations were performed in the multiconfiguration self-consistent field (MCSCF) approach including the N-O and the F-NO bond distances with the FNO bond angle being fixed.The most striking feature of the time-dependent dynamical analysis is a bifurcation of the wave packet near the Franck-Condon point: while one part of the wave packet leaves the inner region of the potential energy surface very rapidly, a second part remains trapped for several periods in an extremely shallow well at short F-NO distances.The direct part leads to a broad background in the absorption spectrum while the trapped portion of the wave packet gives rise to relatively narrow resonances, i.e., well resolved diffuse vibrational structures.The bandwidth decreases with the degree of internal excitation.The calculated spectrum agrees well with the measured one.
Burley, Joel D.,Miller, Charles, E.,Johnston, Harold S.
, p. 377 - 391 (1993)
EFFICIENT PURELY CHEMICAL CW LASER OPERATION
COOL TA,STEPHENS RR
, p. 55 - 58 (1970)
Continuous-wave laser operation at 10. 6U has been achieved in the DF-CO//2 and HF- CO//2 molecular systems by purely chemical means. No external energy sources are required; both lasers operate solely by the simple mixing of bottled gases. Experimental r
Thermally persistent fluorosulfonyl nitrene and unexpected formation of the fluorosulfonyl radical
Zeng, Xiaoqing,Beckers, Helmut,Willner, Helge
, p. 2096 - 2099 (2013/04/23)
Thermally persistent triplet sulfonyl nitrene, FSO2N, was produced in the gas phase in high yields (up to 66%) by flash vacuum pyrolysis of FSO2N3. Surprisingly, no rearrangement of FSO 2N was observed, but the
Endothermic formation of a chemical bond by entropic stabilization: Difluoronitroxide radical in solid argon
Misochko, Eugenii Ya.,Akimov, Alexander V.,Goldschleger, Ilya U.,Boldyrev, Alexander I.,Wight, Charles A.
, p. 405 - 410 (2007/10/03)
Difluoronitroxide radical (F2NO) has been formed in solid argon matrices by successive addition of two diffusing F atoms to NO. This radical exists in dynamic equilibrium with a van der Waals complex (FFNO). Measurements of the equilibrium concentrations as a function of temperature show that the changes in enthalpy and the entropy associated with formation of the F2NO radical are ΔH = 1240 ± 180 J/mol and ΔS = 62 ± 10 J/(mol K). Because both these quantities are positive, the equilibrium favors F2NO only at elevated temperatures. This situation is a rare case in which formation of a chemical bond is stabilized only by an increase in the entropy of the system.
Seven-coordinated pnicogens. Synthesis and characterization of the SbF72- and BiF72- dianions and a theoretical study of the AsF72- dianion
Drake, Greg W.,Dixon, David A.,Sheehy, Jeffrey A.,Boatz, Jerry A.,Christe, Karl O.
, p. 8392 - 8400 (2007/10/03)
The novel seven-coordinated BiF72- and SbF72- dianions have been prepared and characterized. The Cs2BiF7, Rb2BiF7, K2BiF7, and Na2BiF7 salts were obtained in high yield by heating BiF5 with an excess of the corresponding alkali metal fluorides to about 250 °C. Attempts failed to prepare the corresponding BiF83- salts or Li2BiF7 under similar conditions. The [N(CH3)4]2BiF7 salt was obtained by the combination of excess N(CH3)4F with BiF5 in CH3CN solution at -31 °C. The (NO2)2BiF7 salt was prepared from BiF5 and a large excess of liquid FNO at -78 °C and decomposes at room temperature to NOBiF6 and FNO. The corresponding Cs2SbF7, K2SbF7, and [N(CH3)4]2SbF7 salts were also synthesized in a similar fashion, but Na2SbF7 was not formed. The pronounced fluoride ion affinity of SbF6- was further demonstrated by the formation of some Cs2SbF7 when dry CsF and CsSbF6 were ball-milled at room temperature. The BiF72- and SbF72- anions, which are the first examples of binary pnicogen compounds with coordination numbers in excess of six, were characterized by vibrational spectroscopy and ab initio electronic structure calculations. They possess pentagonal bipyramidal, highly fluxional structures of D(5h) symmetry, similar to those of IF7 and TeF7-, which are isoelectronic with SbF72-. Although our theoretical calculations indicate that AsF72- is also vibrationally stable, experiments to prepare this dianion were unsuccessful.
