Excitons in poly(para phenylene vinylene): a quantum-chemical perspective based on high-level ab initio calculations

2016 ◽  
Vol 18 (4) ◽  
pp. 2548-2563 ◽  
Author(s):  
Stefanie A. Mewes ◽  
Jan-Michael Mewes ◽  
Andreas Dreuw ◽  
Felix Plasser
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Quantum Chemical ◽  
Phenylene Vinylene ◽  
High Level ◽  
Quantum Chemical Computations

Exciton analyses of high-level quantum-chemical computations for poly(paraphenylene vinylene) reveal the nature of the excitonic bands in PPV oligomers.

scholarly journals Dipole-dipole polarizability of the cadmium -=SUP=-1-=/SUP=-S-=SUB=-0-=/SUB=- state revisited -=SUP=-*-=/SUP=-

2021 ◽  
Vol 129 (12) ◽  
pp. 1483
Author(s):  
Uwe Hohm
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Oscillator Strength ◽  
Quantum Chemical ◽  
Experimental Results ◽  
Dipole Polarizability ◽  
Static Polarizability ◽  
Dipole Oscillator ◽  
High Level ◽  
Strength Distributions

Experimental results and high-level quantum chemical ab initio calculations of the static polarizability α=α(ω=0)) of the cadmium 1S0 state are still in marked disagreement. Here we analyze this discrepancy by using experimentally determined dipole oscillator strength distributions (DOSD). It will be shown that within this procedure the experimentally determined static polarizability α0 will shift from 49.7± 1.6 au to considerably lower values. We now conclude an experimentally determined polarizability of α0 = 47.5 ± 2.0 au in much better agreement with the latest calculations of α0~ 46 au. Keywords: cadmium, polarizability, DOSD

Configurational Assignment and Conformational Study of Methylglyoxal Bisdimethylhydrazones Derived from the 2-Ethoxypropenal Precursor

2006 ◽  
Vol 59 (3) ◽  
pp. 211 ◽  
Author(s):  
Leonid B. Krivdin ◽  
Lyudmila I. Larina ◽  
Kirill A. Chernyshev ◽  
Natalia A. Keiko
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Experimental Measurements ◽  
Conformational Study ◽  
Lone Pairs ◽  
Configurational Assignment ◽  
Out Of Plane ◽  
High Level

A configurational assignment of the isomeric methylglyoxal bisdimethylhydrazones derived from the 2-ethoxypropenal precursor has been performed based on experimental measurements and high-level ab initio calculations of 1J(C,C) and 1J(C,H) couplings. The results reveal the marked stereochemical dependence upon the orientation of the lone pairs of both nitrogen atoms in different isomers. Methylglyoxal bisdimethylhydrazone is shown to exist in a mixture of the EE and ZE isomers (ca. 75:25), both of which adopt predominant s-trans conformations with minor (up to 8°) out-of-plane deviations.

scholarly journals Geometric and Energetic Data from Ab Initio Calculations of Haloethene, Haloimine, Halomethylphosphine, Haloiminophosphine, Halodiazene, Halodiphosphene and Halocyclopropane

2019 ◽  
Author(s):  
Kridtin Chinsukserm ◽  
Wanutcha Lorpaiboon ◽  
Peerayar Teeraniramitr ◽  
Taweetham Limpanuparb
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Quantum Chemical ◽  
Theoretical Data ◽  
Geometric Optimization ◽  
Basis Set ◽  
Halogenated Compounds ◽  
Wolfram Mathematica

<p>This article presents theoretical data on geometric and energetic features of halogenated compounds of cyclopropane (∆) and ethene (C=C), imine (C=N), methylphosphine (C=P), iminophosphine (N=P), diazene (N=N) and diphosphene (P=P). The data were obtained from <i>ab initio</i> geometric optimization and frequency calculations at HF, B3LYP, MP2 and CCSD levels of theory on 6-311++G(d,p) basis set. Input structures were generated by shell scripts and run by Q-Chem quantum chemical package. The output files were processed to extract geometric and energetic information by Wolfram Mathematica.</p>

scholarly journals Exploration of the NH3–H2 van der Waals interaction by high level ab initio calculations

2008 ◽  
Vol 346 (1-3) ◽  
pp. 237-246 ◽  
Author(s):  
Mirjana Mladenović ◽  
Marius Lewerenz ◽  
Geraldine Cilpa ◽  
Pavel Rosmus ◽  
Gilberte Chambaud
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Van Der Waals ◽  
Van Der Waals Interaction ◽  
High Level

Regular polyhedral molecules. P20 and its inclusion compounds

1998 ◽  
Vol 76 (9) ◽  
pp. 1274-1279 ◽  
Author(s):  
Lubomír Rulísek ◽  
Zdenek Havlas ◽  
Stanislav Hermánek ◽  
Jaromír Plesek
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Inclusion Compounds ◽  
Vibrational Analysis ◽  
Kinetic Stability ◽  
Stabilizing Agents ◽  
Geometrical Properties ◽  
Regular Dodecahedron ◽  
Phosphorus Clusters ◽  
High Level

Based upon the geometrical properties of regular polyhedrons, the possibility of the existence of certain polyhedral molecules composed of only one element is investigated. A very promising candidate - the regular dodecahedron - is selected as the convenient polyhedral structural pattern and phosphorus as the appropriate element. A series of high-level ab initio calculations is performed on the dodecahedral P20 molecule, including predictions of its thermodynamic and kinetic stability, natural bond orbital analysis, vibrational analysis, and inclusion of some elements into the molecular skeleton. Due to the potential stabilizing agents that may eventually form stable inclusion compounds and the estimated high kinetic stability, the question of the possible existence of P20 is answered in the positive.Key words: ab initio calculations, inclusion compounds, P20, phosphorus clusters, polyhedra.

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