Cross-section analysis of the gas-phase potential surface for the addition of water to formaldehyde. A theoretical study of the energetics of proton transfer as a function of .DELTA.pKA

1990 ◽  
Vol 112 (4) ◽  
pp. 1319-1321 ◽  
Author(s):  
Shmaryahu Hoz ◽  
Kiyull Yang ◽  
Saul Wolfe
Keyword(s):  
Proton Transfer ◽  
Gas Phase ◽  
Cross Section ◽  
Theoretical Study ◽  
Potential Surface ◽  
Section Analysis

Interaction character and proton transfer mechanism of [HPro(C<sub>1</sub>)]<sup>+</sup> and [Sac]<sup>-</sup> in the gas phase: A theoretical study

2013 ◽  
Vol 43 (10) ◽  
pp. 1363-1374
Author(s):  
Wei GUAN ◽  
Ning YU ◽  
YuanYuan ZHANG ◽  
Yang WU ◽  
Qi YANG ◽  
...  
Keyword(s):  
Proton Transfer ◽  
Gas Phase ◽  
Theoretical Study ◽  
Transfer Mechanism

Theoretical study on gas-phase proton transfer reactions between π-proton-donor and π-acceptor systems

2001 ◽  
Vol 348 (1-2) ◽  
pp. 95-101 ◽  
Author(s):  
Zheng-wang Qu ◽  
Hui Zhu ◽  
Shu-hua Ma ◽  
Hong Xu ◽  
Rubo Zhang ◽  
...  
Keyword(s):  
Proton Transfer ◽  
Gas Phase ◽  
Theoretical Study ◽  
Proton Donor ◽  
Transfer Reactions ◽  
Proton Transfer Reactions

Excited State Proton Transfer in Guanine in the Gas Phase and in Water Solution:  A Theoretical Study

2005 ◽  
Vol 109 (34) ◽  
pp. 7775-7780 ◽  
Author(s):  
M. K. Shukla ◽  
Jerzy Leszczynski
Keyword(s):  
Excited State ◽  
Proton Transfer ◽  
Gas Phase ◽  
Theoretical Study ◽  
Water Solution ◽  
Excited State Proton Transfer

INTRAMOLECULAR CHARGE TRANSFER AND PHOTOISOMERIZATION OF THE DCM STYRENE DYE: A THEORETICAL STUDY

2008 ◽  
Vol 07 (04) ◽  
pp. 719-736 ◽  
Author(s):  
XUEFEI XU ◽  
RUIQIN ZHANG ◽  
ZEXING CAO ◽  
QIANER ZHANG
Keyword(s):  
Gas Phase ◽  
Energy Surface ◽  
Theoretical Study ◽  
Potential Surface ◽  
Polar Solvent ◽  
Intramolecular Charge Transfer ◽  
Structures And Properties ◽  
Experimental Values ◽  
Intramolecular Rotation ◽  
Good Agreement

Structures and properties of the low-lying states in 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) have been investigated theoretically. Calculations show that the dimethylamino and dimethylanilino twisted conformations of DCM on the potential energy surface of the first excited state ( S 1) have relatively high stabilities and remarkable intramolecular charge transfers (ICT). Both structures can serve as candidates for the red-shifted emissive state in polar solvent. In particular, the dimethylanilino twisted ICT state has been predicted to have a dipole moment increment of 20 Debye with respect to the ground state by CASSCF calculations, in good agreement with the suggested experimental values. The optimized geometry of the S 1 state exhibits a long central CC bond of 1.458 Å, which makes the trans–cis isomerization quite facile through intramolecular rotation around the central CC bond on the S 1 potential surface. The S 1 state is a precursor to the formation of the ICT emissive state and photoinduced trans–cis isomerization. The S 1/ S 0 crossing in polar solvent and avoid-crossing in the gas phase as well as in non-polar solvent are involved in the trans–cis isomerization process. The presence of an early S 1/ S 0 crossing in the strong polar solvent reduces the isomerization efficiency.

scholarly journals A theoretical study of the intramolecular proton transfer and calculation of the nucleus independent chemical shift in juglone and some of its derivatives

2011 ◽  
Vol 76 (6) ◽  
pp. 879-890 ◽  
Author(s):  
E. Vessally ◽  
Ehsan Fereyduni ◽  
M. Kamaee ◽  
S. Moradi
Keyword(s):  
Chemical Shift ◽  
Proton Transfer ◽  
Dft Calculations ◽  
Gas Phase ◽  
Ground State ◽  
Theoretical Study ◽  
Intramolecular Proton Transfer ◽  
Gauge Transformations ◽  
Nucleus Independent Chemical Shift ◽  
Nuclear Independent Chemical Shift

In the present study, first, the intramolecular proton transfer (IPT) process of juglone and its derivatives were theoretically investigated in the gas phase and the effect of electron-withdrawing and electronreleasing substituents in different positions of the phenyl and benzoquinone rings of juglone on the IPT process was studied in which the geometries, energies and thermodynamic functions of the compounds were obtained using DFT calculations at the B3LYP/6-31+G(2d,p) level. Next, the influence of IPT on changing the aromaticity of the phenyl and benzoquinone rings was investigated. To determine the aromaticity of the rings, nuclear independent chemical shift (NICS) values were calculated for the ground state and transition state structures (GS1,TS,GS2) using the continues set of gauge transformations (CSGT) procedure at the B3LYP/6-311+G(2d,p) level.

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