Ionization potentials 1,3-butadiene

Platinum-cobalt alloy, enthalpy of formation, 144 Polarizability, of carbon, 75 of hydrogen molecule, 65, 75 and ionization potential data, 70 Polyamide, 181 Poly butadiene, 170, 181 Polydispersed systems, 183 Polyfunctional polymer, 178 Polymerization, of butadiene, 163 of solid acetaldehyde, 163 of vinyl monomers, 154 Polymers, star-shaped, 183 Polymethyl methacrylate, 180 Polystyrene, 172 Polystyril carbanions, 154 Potential barriers of internal rotation, 368, 374... 

Fia. 21. Improvement in agreement between calculated and observed ionization potentials for simple w systems as between values derived on the simple H.M.O. basis (left-hand end of arrows) and those derived using the oj technique (right-hand end of arrows). See text. 1, Methyl 2, Allyl 3, Pentadienyl 4, Benzyl 6, Ethylene 6, Butadiene 7, Benzene 8, Styrene 9, Naphthalene 10, Fhenanthrene. 

Other characteristics of conjugated molecules can also be indicated the shift of the UV absorption maximum of butadiene and other polyenes to the longwave region of spectrum as compared to ethylene, the lowering of ionization potentials, and so on. In short,. there is much evidence pointing to the fact that the properties of conjugated systems are determined by the interaction of multiple bonds. 

Enokida et al. (1990) measured hole mobilities of 2,5-bis(p-diethylamino-pheny 1)-1,3,4-oxadiazole, 1 -(3 -methylpheny 1)-1,2,3,4-tetrahydroquinoline-6-carboxylaldehyde-1. l -diphenylhydra/.onc, and l,l-bis(p-diethylaminophenyl)-4,4-diphenyl-l,3-butadiene doped polymers. The polymer was PC. At 5.0 x 105 V/cm, the mobilities were 5.7 x 10-8,1.2 x 10-6, and 8.7 x 1(>6 cm2/Vs for the oxadiazole, hydrazone, and butadiene doped polymers, respectively. The authors attributed the differences in mobility to differences in ionization potential. The ionization potentials vary from 5.11 to 5.74 eV. 

There have been several attempts to relate mobilities to ionization or oxidation potentials (Enokida et al., 1990 Scott et al., 1990 Kanemitsu et al., 1991, 1992 Kitamura and Yokoyama, 1991). Scott et al. studied a series of hydrazone compounds in a polyarylate. The oxidation potentials of the donor compounds varied from 0.53 to 1.04 V. The results showed that the zero-field mobilities increase with increasing oxidation potential. In contrast, Enokida et al. investigated a series of butadiene, hydrazone, and oxadiazole compounds doped into a PC and concluded that the mobilities increased with decreasing ionization potential. Kitamura and Yokoyama studied a series of hydrazone compounds in a PC and concluded that the mobilities were independent of the ionization potential. While the reason for these discrepancies is not clear, it should be noted that the study of Scott and coworkers involved zero-field... 

Fig. 52. Effect of additive ionization potentials on the pliotoluminescence intensity ( ) and the rate R) of the photocatalytic hydrogenation of the added unsaturated hychocarbons with H2O on TiOi (O). /q and are maximum photoluminescence intensities, respectively, under vacuum (or in Ni) and in the presence of added compounds 1, 1,3-butadiene 2, 1-butylene 3, propylene 4,1-butyne 5,1-propyne 6, ethylene 7, acetylene. Photoluminescence spectra recorded at 77 K photocatalytic reactions carried out at 298 K [reproduced with permission from Anpo el al. (223)].

Table 1.2 The Butadiene tc-system, with AN=N =4, frontier energetic quantities, ionization potential IP), electron affinity EA), electronegativity (x), and chemical hardness (rj) of Eqs. 1.7 and 1.8 - in electron volts (eV), and the resulted parabolic energy of Eq. 1.98, alongside with the 7t-related energy based on the Hiickel simplified (with Coulomb integrals set to zero, a = 0) expression of (1.97) for the experimental/Hiickel method and on the related energy form of Eq. 1.101 and the other semi-empirical methods CNDO, INDO, MINDO, MNDO, AMI, PM3, ZINDO) as described in the previous section - expressed in kilocalories per mol (kcal/mol) their ratio in the last column reflects the value of the actual departure of the electronegativity and chemical hardness parabolic effect from the pi-bonding energy, while for the first (Exp Hiickel) line it expresses the resonance contribution (and a sort of P factor integral) in (1.97) for the tt-bond in this system the eV to kcal/mol conversion follows the rule 1 eV = 23.069 kcal/mol...

The ultraviolet spectra of crowded olefins and substituted butadienes have been studied the sign of the Cotton effect has been related to the chirality of a series of w-molecular complexes of olefins with tetracyanoethylene the sign of the chiral-optical effects of non-planar heteroannular cisoid dienes is opposite to that predicted from the diene rule. Studies of linear and circular dichroism in mono-olefins and magnetic circular dichroism of conjugated olefins have been made, and the experimental ionization potentials of fourteen alkenes have been correlated with the inductive effects of substituents. ... 

The ordering of the reactant orbitals is obtained from ionization potentials of molecular oxygen and butadiene. The reactant configuration with singly occupied MOs jfi and COj) correlates with a highly excited product configuration, while the configuration Ttf - Ttf with doubly occupied MOs... 

Due to the symmetry, observed in the classical L.C.A.O. molecular orbital calculations, of the h.o.m.o. (related to the ionization potential) and of the l.e.m.o. (related to the ease of acceptance of an electron in reduction) in certain types of compounds, e.g., conjugated hydrocarbons (complete symmetry when overlap is neglected, less complete when it is included), any property related, i.e., proportional, to one will be proportional to the other (this will not hold in more refined treatments). Thus, the theoretical r-ionization potentials of hydrocarbons are linearly proportional to the values for diphenyl, naphthalene, phenanthrene and anthracene the point for butadiene deviates slightly from the straig[ht line relation, while that for st5nrene deviates markedly. Such incidental correlations, due primarily to mathematical S3munetry rather than to fundamental physical significance, must be watched for carefully. The same remark is valid for a proposed correlation" between absorption spectra and half-wave potentials (cf. reference 21). 

Mukherjee D, Moitra RK, Mukhopadhyay A. Applications of a non-perturbative many-body formalism to general open-shell atomic and molecular problems calculation of the ground and the lowest ir-ir singlet and triplet energies and the first ionization potential of trans-butadiene. Mol Phys. 1977 33 955-969. 

Copolymers of 2,3-epoxypropyl methacrylate and butadiene prepared by solution free radical polymerization were tested as potential candidates for electrom negative resists.The sensitivity of the copolymers to ionizing radiation was determined with a linear accelerator.The experimental data were treated according to the Saito-Inokuti statistical theory.The calculated crosslinking yield values, G(x),were dependent an... 

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