نتایج جستجو برای: electron delocalization

تعداد نتایج: 310383  

Journal: :journal of the iranian chemical research 0
ewa d. raczyńska department of chemistry, warsaw university of life sciences (sggw), 02-776 warszawa, poland małgorzata hallmann department of chemistry, warsaw university of life sciences (sggw), 02-776 warszawa, poland kinga duczmal department of chemistry, warsaw university of life sciences (sggw), 02-776 warszawa, poland

amide-iminol tautomerism was studied for ionized oxamic acid (oa+•) in the gas phase using thedft method with the ub3lyp functional and various basis sets {6-31++g(d,p), 6-311+g(d,p), and augcc-pvdz}. among twenty tautomers-rotamers possible for oa+•, eleven isomers were found to bethermodynamically stable. similarly as for the neutral molecule, ionization (oa → oa+• + e) favors theamidization ...

2016
V. Abramavicius V. Pranculis A. Melianas O. Inganäs V. Gulbinas D. Abramavicius

Photo-induced charge transfer at molecular heterojunctions has gained particular interest due to the development of organic solar cells (OSC) based on blends of electron donating and accepting materials. While charge transfer between donor and acceptor molecules can be described by Marcus theory, additional carrier delocalization and coherent propagation might play the dominant role. Here, we d...

2003
Chérif F. Matta Jesús Hernández-Trujillo

We show that the delocalization indices calculated within the framework of the quantum theory of atoms in molecules provide an excellent basis for the definition of a bond order in polycyclic aromatic hydrocarbons. We show that the two-electron information contained within the delocalization index can be estimated from the electron density at the bond critical point, a mapping that has no a pri...

Journal: :Journal of computational chemistry 2002
Xavier Fradera Miquel Solà

Localization and delocalization indices derived in the framework of the quantum Atoms in Molecules theory have recently been used to analyze the electron-pair structure of closed-shell molecules. Here we report calculations of localization and delocalization indices for open-shell molecules at the Hartree-Fock (HF) level. Several simple doublet and triplet radical molecules are studied. In gene...

2011
J. David Carey Simon J. Henley

The electronic properties of disordered carbon based materials can be discussed in terms of the clustering of the sp 2 carbon phase and delocalization of the electron wavefunction. In smooth amorphous carbon thin films this results in a mixed phase material of conductive sp 2 clusters embedded in an electrically insulating sp 3 matrix. The delocalization of the electron wavefunction associated ...

Journal: :Physical chemistry chemical physics : PCCP 2015
Marcos Mandado Nicolás Ramos-Berdullas

The unusual aromatic stability of cyclic bicalicene has been suggested to come from a tetraionic structure, where positive and negative charges are located on the cyclopropene and cyclopentadiene rings, respectively. Energetic, magnetic, geometric and electron delocalization analysis performed on a series of bicalicene derivatives, incorporating different electron donating and withdrawing group...

1999
Richard Berkovits

The localization length of a low energy tightly bound electron-hole pair (excitons) is calculated by exact diagonalization for small interacting disordered systems. The exciton localization length (which corresponds to the thermal electronic conductance) is strongly enhanced by electron-electron interactions, while the localization length (pertaining to the charge conductance) is only slightly ...

Journal: :Ultramicroscopy 2007
R F Egerton

We discuss various factors that determine the performance of electron energy-loss spectroscopy (EELS) and energy-filtered (EFTEM) imaging in a transmission electron microscope. Some of these factors are instrumental and have undergone substantial improvement in recent years, including the development of electron monochromators and aberration correctors. Others, such as radiation damage, delocal...

2017
Sabine Richert George Bullard Jeff Rawson Paul J Angiolillo Michael J Therien Christiane R Timmel

The influence of electronic symmetry on triplet state delocalization in linear zinc porphyrin oligomers is explored by electron paramagnetic resonance techniques. Using a combination of transient continuous wave and pulse electron nuclear double resonance spectroscopies, it is demonstrated experimentally that complete triplet state delocalization requires the chemical equivalence of all porphyr...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید