Reaction dynamics during warm-up of matrix-isolated cyanogen azide after photolysis

Dissociation of Cyanogen Azide: An Alternative Route to Synthesis of Carbon Nitride

“…Correcting for zero-point energy, we find transitionstate barriers of 1.19 and 1.18 eV (relative to the minimum in the 1 A′ surface for NCN 3 ) at the CBS-Q and B3LYP levels of theory, respectively. These calculated barrier heights are significantly larger than previously determined values for FN 3 and ClN 3 , in qualitative agreement with experimental evidence 6,7,12 that NCN 3 has greater thermal stability (decay time on the order of a week at ambient temperature relative to hours or fractions thereof for ClN 3 and FN 3 , respectively). On the basis of the calculated barrier height, it appears that NCN 3 can be efficiently dissociated in single collisions with vibrationally excited N 2 molecules that are either at or above the V ) 4 energy level.…”

“…On the basis of commonalities in the above research data, it seemed feasible that a rich source of NCN could also be obtained from analogous dissociation of the (X = CN) pseudohalogen azide. Prior matrix isolation and photolysis studies of cyanogen azide (NCN 3 ) by Milligan and later by Krogh also suggested this possibility. , Rapid self-annihilation of NCN radicals via the reaction (2NCN → 2CN + N 2 ), however, constitutes a potential difficulty in this scheme that is also implied by analogy to the known kinetics of NF* and NCl* decay following dissociation of the corresponding parent azides. , …”

“…Prior matrix isolation and photolysis studies of cyanogen azide (NCN 3 ) by Milligan and later by Krogh also suggested this possibility. 11,12 Rapid self-annihilation of NCN radicals via the reaction (2NCN f 2CN + N 2 ), however, constitutes a potential difficulty in this scheme that is also implied by analogy to the known kinetics of NF* and NCl* decay following dissociation of the corresponding parent azides. 6,7 In this work, a primary stream of helium (He) the-fly with a secondary stream of donor NCN 3 molecules and He diluent in a low-pressure flow-tube reactor.…”

Quantum chemical treatment of cyanogen azide and its univalent and divalent ionic forms

“…Experimental studies show that the N1 N2 bond is the weakest bond in the molecule [39]. According to the present calculations, the bond rupture of this bond takes place in the divalent anionic form.…”

Photochemistry of small molecules in low-temperature matrixes

“…Such a mechanism was conclusively demonstrated in the photolysis of NCN:109 (35) CNN, which can also be generated via photolysis of other carbon-atom sources in nitrogen (e.g., C302 or CH4) has been reinvestigated recently. 75,110,111 The isomerization of the Renner-Teller molecules CCN and CNC is less well established. IR and UV/vis absorption studies of the photolysis of CH3CN with a hydrogen-discharge lamp indicate production of CNC with inconclusive evidence for CCN.…”