The reactions of O(1D) atoms with fluorides have been investigated by time-resolved laser magnetic resonance (LMR). O(1D) atoms were produced by the dissociation of ozone with an excimer laser (KrF, 248 nm). By monitoring Cl atoms (when HCl or Cl2 is added) or FO radicals, the rate constants for total removal of O(1D) (×10−11 cm3/s) by HF(5.1±1.0), F2(0.81±0.20), XeF2(16±3.0), NF3(1.2±0.25), and CF4(<0.016) have been determined at 298 K. Reaction rate constants (×10−11 cm3/s) have been obtained for HF(1.5±0.3), F2(0.81±0.2), XeF2(14±3.0), and NF3(1.0±0.3). The deactivation of O(1D) by HX (X=F, Cl, Br) is discussed. Ab initio calculations have been performed with the aim of qualitative comparison of deactivation of O(1D) by F2 and Cl2.

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Through-conjugation for a wide range of 1, 8-diamino-4,5-dinitronaphthalenes (N-acylated, N-alkylated, N,N 0 -bridged, N-heterocyclic, and N-deprotonated compounds) was for the first time quantified in solution by means of ultravioletvisible and proton nuclear magnetic resonance spectroscopy and compared with that of the simpler naphthalene and benzene push-pull systems. Surprisingly, an extent of conjugation in 1,8-diamino-4-nitro-and 1,8-diamino-4,5dinitronaphthalenes measured in dimethyl sulfoxide is commensurable. On the whole, the repulsive peri-interactions between the amino groups in systems with N-alkylated and N-deprotonated amino groups are more favorable for an effective D-p-A charge transfer than in N,N 0 -bridged compounds (perimidines, 2,3-dihydroperimidines and perimidin-2-ones). The best electron donors from peri-positions are pyrrolidin-1-yl and methylamido groups. The conclusions obtained from solution studies were deepened by solid-state X-ray experiments for a number of push-pull naphthalenes, including 6,7-dinitroperimidine N-anion and two representatives of 4,5-diaminonaphthalene-1,8-dicarbaldehydes. In particular, they helped to trace changes in the bond order redistribution and twisting of the naphthalene core. The latter reaches a record value of 27 for 4,5-dinitro-1,8-di(pyrrolidin-1-yl)naphthalene.

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