نتایج جستجو برای: am1 semi empirical quantum mechanics

تعداد نتایج: 670490  

Journal: :حکمت و فلسفه 0
علی پایا هیئت علمی دانشگاه علامه طباطبایی

the aim of the present paper is to sbo» that anti-realism in science, 1vhich has a1;guab/y become more fashionable in recentyears, contrary to tuha: its proponents assert, cannot make use of quantum mechanics and its impressiue achievements as a frump card in justifying its claims. i will argue that scientific anti-realism far from providing scientific communiry with a progressive methodologica...

Journal: :journal of physical & theoretical chemistry 2005
issa yavari hassan kabiri-fard

the results of mndo, am1 and pm3 semi-empirical calculations and hf/6-31g*, mp/6-31g*, mp2/6-311+g**, and b3lyp/6-311g** and qcisd/6-31g* ab initio methods for angle strain and conjugation effects in twist-boat, boat, and half-chair geometries of (z,z,z)-cycloocta-1,3,5-triene indicate that all methods, except pm3, predict wrong ordering of the conformations.

2017
Zlatko Majlinger Milan S. Dimitrijević Zoran Simić

Regularities and systematic trends among the Stark widths of 18 Zr IV spectral lines obtained by modified semiempirical approach have been discussed. Also we compared those calculated Stark broadening parameters with estimates according to Cowley, Purić et al. and Purić and Šćepanović and checked the possibility to find some new estimates. It is demonstrated as well that the formula of Cowley (...

1999
Sung Y. Hong

We have performed a quantum-chemical investigation on the conformations and electronic properties of a variety of methoxy-substituted poly(p-phenylenevinylenes) (PPVs) to elucidate the effects of alkoxy substitution. Geometrical parameters for the polymers were fully optimized through Austin Model 1 (AM1) semi-empirical Hartree-Fock (HF) band calculations. Electronic properties of the polymers ...

2007
Erol Eroglu Selami Palaz Oral Oltulu Hasan Turkmen Cihat Ozaydın

Several quantum-mechanics-based descriptors were derived for a diverse set of 48 organic compounds using AM1, PM3, HF/6-31+G, and DFT-B3LYP/6-31+G (d) level of the theory. LC50 values of acute toxicity of the compounds were correlated to the fathead minnow and predicted using calculated descriptors by employing Comprehensive Descriptors for Structural and Statistical Analysis (CODESSA) program....

2003
YINGBIN GE JOHN D. HEAD

Previously we searched for the ab initio global minima of several SixHy clusters by a genetic algorithm in which we used the AM1 semiempirical method to facilitate a rapid energy calculation for the many different cluster geometries explored. However, we found that the AM1 energy ranking significantly differs from the ab initio energy ranking. To better guarantee locating the ab initio global m...

Journal: : 2021

We are presenting the results obtained by computing different toxicity indices for some of newest JWH synthetic cannabinoids, using (Q)SAR models, ADME(T) predictions, simulations NMR spectral techniques and other computational dedicated software packages forensic analytical tools. have examined main physical chemical properties evaluated behavioral neurotoxicity pharmacokinetic profile 16 amin...

2014
Pablo Martín-Ramos Manuela Ramos Silva Pedro S. Pereira Silva Jesus Martín-Gil

An Erbium(III) quaternary chelate, nitratebis(2,4-hexanedionate)mono(2,2-bipyridine) erbium(III), has been synthesized and its structure elucidated by X-ray diffraction. There are two independent lanthanide complexes in the asymmetric unit cell. The ligands coordinate the Er(III) in a square anti-prismatic geometry. In the theoretical part of this study, semi-empirical quantum chemistry methods...

2016
P. Chamorro-Posada

Semi-empirical quantum chemistry methods offer a very interesting compromise between accuracy and computational load. In order to assess the performance of NDDO methods in the interpretation of terahertz spectra, the low frequency vibration modes of three crystalline materials, namely, polyethylene, poly(vinylidene fluoride) form II and α-D-glucose have been studied using the PM6 and PM7 Hamilt...

2014
Tomás Bouchal Radka Svobodová Vareková Tomás Racek Crina-Maria Ionescu Stanislav Geidl Ales Krenek Jaroslav Koca

Partial atomic charges describe the distribution of electron density in a molecule, and therefore they provide clues regarding the chemical behaviour of molecules. Atomic charges are frequently used in molecular modelling applications such as molecular dynamics, docking, conformational searches, binding site prediction, etc. Recently, partial atomic charges have also become popular chemoinforma...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید