The Photoelectron Spectrum of 1-Bromonortricyclene

1985 ◽  
Vol 38 (1) ◽  
pp. 69 ◽  
Author(s):  
EW Della ◽  
PE Pigou ◽  
MK Livett ◽  
JB Peel

The He I photoelectron spectrum of 1-bromotricyclo[2.2.1.02.6] heptane (1- bromonortricyclene ) is compared with that of the parent alkane . Extensive conjugation between bromine and alkane orbitals in the low ionization-energy range produces a complex band pattern which is adequately described by ab initio valence-electron molecular orbital calculations. Consequently 1-bromo-nortricyclene presents a rare example of an alkyl halide in which the halogen character is neither highly localized nor smeared over a high density of states.

1979 ◽  
Vol 170 (3) ◽  
pp. 285-292 ◽  
Author(s):  
Rolf Gleiter ◽  
Michael C. Böhm ◽  
Arne Haaland ◽  
Ragnar Johansen ◽  
Janusz Lusztyk

1979 ◽  
Vol 32 (4) ◽  
pp. 719 ◽  
Author(s):  
F Carnovale ◽  
T Gan ◽  
JB Peel

The He I and He II spectra obtained for chlorodimethylamine (CH3)2NCl, and bromodimethylamine (CH3)2NBr, complete the study of the N-chloro and N-bromo derivatives of the small amines. The valence photoelectron spectra are interpreted with the aid of SPINDO molecular orbital calculations. Trends in the observed ionization energies for both series of small halo amines are described in terms of variations in inductive and resonance effects, the latter particularly concerning the nN/nx lone-pair interactions observed in the low ionization energy range.


Ab initio molecular orbital calculations are used to explore additivity in the conformational energies of poly-substituted ethanes in terms of conformational energies of ethane and appropriate mono- and 1,2-di-substituted derivatives. Such relations would allow complex calculations for poly-substituted ethanes to be replaced by much simpler ones on a small number of parent molecules. General expressions for the linear combinations are derived from the assumption that interactions between vicinal substituents are pairwise additive and depend only on the vicinal dihedral angle. The additivity scheme is tested for 15 ethanes, di-, tri- or tetrasubstituted by cyano and methyl groups and for a smaller number of fluoroethanes. Additivity applies to within 0.1- 0.3 k J mol -1 in the methylethanes and mostly to within about 0.7- 0.8 kJ mol -1 in cyanoethanes. Large deviations are found among the geminally substituted fluoroethanes. It is suggested that the additivity approximation is most successful in the absence of strongly interacting geminal groups. Predictions are made of conformational energies of ten hexa(cyano- and methyl-) substituted ethanes.


1981 ◽  
Vol 36 (11) ◽  
pp. 1246-1252 ◽  
Author(s):  
Michael H. Palmer ◽  
Isobel Simpson ◽  
J. Ross Wheeler

The photoelectron spectra of the tautomeric 1,2,3,- and 1,2,4-triazole and 1,2,3,4-tetrazole systems have been compared with the corresponding N-methyl derivatives. The dominant tautomers in the gas phase have been identified as 2 H-1,2,3-triazole, 1 H-1,2,4-triazole and 2H-tetrazole.Full optimisation of the equilibrium geometry by ab initio molecular orbital methods leads to the same conclusions, for relative stability of the tautomers in each of the triazoles, but the calculations wrongly predict the tetrazole tautomerism.


2000 ◽  
Vol 660 ◽  
Author(s):  
Wataru Sotoyama ◽  
Tomoaki Hayano ◽  
Hiroyuki Sato ◽  
Azuma Matsuura ◽  
Toshiaki Narusawa

ABSTRACTWe developed a method to predict the charge transport (CT) type (hole or electron) in molecular materials that uses molecular orbital calculations. The hole-and-electron-mobility ratios of molecular materials were calculated based on molecular structural reorganization energies in a charge hopping process. The CT types predicted from the calculated mobility ratios agreed with those experimentally obtained in seven of the eight model molecules.


2013 ◽  
Vol 433 ◽  
pp. 012035
Author(s):  
Kazuya Nomura ◽  
Ryota Hoshino ◽  
Yasuhiro Hoshiba ◽  
Victor I Danilov ◽  
Noriyuki Kurita

Sign in / Sign up

Export Citation Format

Share Document