Decomposition Mechanism of 1,2-Dioxetane

1974 ◽  
Vol 52 (23) ◽  
pp. 3837-3843 ◽  
Author(s):  
Gene Barnett
Keyword(s):  
Thermal Decomposition ◽  
Molecular Orbital ◽  
Equilibrium Structure ◽  
Decomposition Mechanism ◽  
Correlation Diagram ◽  
Molecular Orbital Calculations ◽  
Temperature Dependent ◽  
Planar Configuration ◽  
Orbital Correlation

An orbital correlation diagram was constructed for the thermal decomposition of 1,2-dioxetane into products that allow chemiluminescence. A decomposition mechanism is proposed that gives a temperature dependent rupture of the OO bond, thus allowing ring twisting which is followed by the rupture of the CC bond. This mechanism is consistent with results of the thermochemical analysis for this type of reaction. The equilibrium structure of 1,2-dioxetane was determined from the molecular orbital calculations and gave a planar configuration for the COOC ring.

Information from stereospecific spin–spin couplings about the relative absorptivities of the hydroxyl stretching bands in 2-iodophenol solutions

1981 ◽  
Vol 59 (21) ◽  
pp. 3021-3025 ◽  
Author(s):  
Ted Schaefer ◽  
Rudy Sebastian ◽  
Timothy A. Wildman
Keyword(s):  
Free Energy ◽  
Molecular Orbital ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Molecular Orbital Calculations ◽  
Temperature Dependent ◽  
Hydroxyl Proton ◽  
Spin Coupling Constants ◽  
Cis And Trans ◽  
Spin Spin Coupling

The stereospecific spin–spin coupling constants between the hydroxyl proton and the ring protons for 2-iodophenol in various solvents yield some free energy differences between the cis and trans conformations of this molecule at 305 K. Comparison with areas of the hydroxyl stretching bands in the same or similar solvents shows that the ratio of the absorptivity coefficients for the two conformers is sensitive to solvent. It is suggested that this ratio is temperature dependent and therefore apparent enthalpy differences must be considered tentative for at least some solutions. Molecular orbital calculations are consistent with the arguments concerning the absorptivity coefficients.

scholarly journals Super-Exchange Interaction in a Chair-Piperazine Bridged Dicopper(II/II) Complex: Synthesis, Crystal Structure, Magnetic Properties and Molecular Orbital Calculations

2006 ◽  
Vol 61 (3) ◽  
pp. 237-242 ◽  
Author(s):  
C. T. Zeyrek ◽  
A. Elmali ◽  
Y. Elerman
Keyword(s):  
Molecular Orbital ◽  
Exchange Coupling ◽  
Binuclear Complex ◽  
Tridentate Ligand ◽  
Molecular Orbital Calculations ◽  
Inversion Symmetry ◽  
Coupling Constant ◽  
Temperature Dependent ◽  
Semi Empirical ◽  
Super Exchange Interaction

Abstract Reaction of the /i-bis(tridentate) ligand H3L' (L' = 1,3-bis[N-(5-cliloro-2-hydroxybenzylidene)- 2-ainiiioetliylene]-2-(5-cliloro-2-hydroxy!phenyl)iniidazoliduie) with eopper(II) chlonde diliydrate gives the chair-piperazine bridged complex [Cu2(μ-L)Cl2]. The halves of the binuclear complex are related by crystallographic inversion symmetry. The intramolecular Cu ・・・Cu separation is 6.954(3) Å. Temperature-dependent magnetic susceptibility measurements of the complex show a weak intramolecular antiferromagnetic eouphng. The super-exchange coupling constant (J) is - 10.5 cm-1. Semi-empirical extended Huckel molecular orbital (EHMO) calculations have been performed in order to gain msight into the molecular orbitals that participate in the super-exchange pathway.

Photoelectron Spectroscopic Studies of Some Substituted Borotrans

1987 ◽  
Vol 40 (5) ◽  
pp. 803 ◽  
Author(s):  
JB Peel ◽  
RG Rothwell ◽  
DX Wang
Keyword(s):  
Thermal Decomposition ◽  
Ab Initio ◽  
Gas Phase ◽  
Molecular Orbital ◽  
Spectroscopic Studies ◽  
Photoelectron Spectra ◽  
Basis Sets ◽  
Molecular Orbital Calculations ◽  
Phase Measurements ◽  
Dative Bond

The HeI photoelectron spectra of a series of borotrans have been measured. Ab initio molecular orbital calculations using minimum basis sets were performed on the six molecules in this study, by using geometries based on the known structure of the parent borotran, a tricyclic system containing a relatively short B←N dative bond. Temperatures up to 312� were required for the gas-phase measurements and considerable thermal decomposition was observed in two cases. The lowest-energy photoelectron bands are assigned to combinations of oxygen orbitals of the BO3 unit, but the B←N bonding electrons cannot be accurately located in the spectra.

Interactions between Methylene Blue and Pullulan According to Molecular Orbital Calculations

2020 ◽  
Vol 140 (11) ◽  
pp. 529-533
Author(s):  
Pasika Temeepresertkij ◽  
Saranya Yenchit ◽  
Michio Iwaoka ◽  
Satoru Iwamori
Keyword(s):  
Methylene Blue ◽  
Molecular Orbital ◽  
Molecular Orbital Calculations
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