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AMPAC Faster. Smarter. Just better. Feature AMPAC 9 MOPAC 2007 Graphical User Interface (GUI) Molecule Building / Viewing ▪ Visual display of properties, surfaces, MOs ▪ Animation of reaction coordinates and vibrations ▪ Gaussian03 – shares common interface ▪ Graphic images for publication ▪ Submit and manage jobs from the GUI ▪ Read pdb files and accurately complete hydrogens ▪ Semiempirical Methods AM1, MNDO, MINDO3, PM3, MNDO/d, RM1, PM6 ▪ ▪ SAM1 (transition metals Fe and Cu), MNDOC ▪ Geometry Optimization and SCF Convergence Automatic Heuristic SCF Convergence ∆ ▪ RHF/UHF ▪ ▪ TRUSTE and TRUSTG geometry optimization ∆ ▪ ▪ Eigenvector Following (EF) ▪ CHN and LTRD transition state location methods ∆ ▪ PATH, IRC for potential surfaces and reaction pathways ▪ Reaction pathway definition ▪ GRID 2D reaction pathway investigation ▪ LFORCE for rapid characterization of TSs and minima ▪ Sparse matrix method for large molecules * ▪ Additional Methods Configuration Interaction (CI) ∆ ▪ Selected State Optimized CI ∆ ▪ Analytic CI Gradients and higher spin multiplicities (20) ∆ ▪ Simulated Annealing for Multiple Minima Searches ▪ AMSOL Method for Solvated Molecules ▪ COSMO Solvation Method ▪ ▪ Tomasi Solvation Method ▪ Property Calculations Thermodynamic Properties ▪ ▪ Unpaired Electron Spin Density ▪ ▪ Population Analysis: Coulson / Mulliken / ESP ▪ ▪ Non-linear Optical Properties ▪ Polymers and solid states ▪ Limited molecular dynamics ▪ Compatibility and Support Fully Compatible with CODESSA™ QSAR Program ▪ Multiple File formats for read/write (mol, mol2, G03, pdf, CIF) ▪ Manual: new, fully updated and indexed in hypertext format ▪ Updating and addition of new features regularly ▪ Customer Support - knowledgeable and available ▪ Generous site-licensing for academics ▪ * Under active development. Common feature enhanced and improved in AMPAC. ∆ AMPAC much faster and more reliable .

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Semiempirical Implementations of Molecular
Semiempirical Implementations of Molecular Orbital Theory How one can make Hartree-Fock theory less computationally intensive without much sacrificing its accuracy? The most demanding step – calculation of two-electron (four-index) integrals (J and K integrals) appearing in the Fock matrix elements (N4 where N is the number of basis functions). One way to save time – to estimate their value accurately in an a priori fashion and thus to avoid numerical integration. Coulomb integrals measure the repulsion between electrons in regions of space defined by the basis functions. When the basis functions in the integral for one electron are very far from the basis functions for the other, the value of that integral will approach zero. In a large molecule, one might be able to avoid the calculation of a very large number of integrals simply by assuming them to be zero. HF theory is intrinsically inaccurate as it does not include correlation energy. Therefore, modifications of the theory introduced in order to simplify its formalism may actually improve it, provided the new approximations somehow introduce an accounting for correlation energy. Most typically, such approximations involve the adoption of a parametric form for some aspect of the calculation where the parameters involved are chosen so as best reproduce experimental data – ‘semiempirical’. Another motivation for introducing semiempirical approximation into HF theory was to facilitate the computation of derivatives (gradients, Hessians) so that geometries could be more efficiently optimized. Extended Hückel Theory Before considering semiempirical methods we revisit Hückel theory: H11 − ES11 H12 − ES12 L H1N − ES1N H21 − ES21 H22 − ES22 L H2N − ES2N = 0 M M O M H − ES H − ES H − ES N1 N1 N2 N 2 L NN NN The dimension of the secular determinant depends on the choice of the basis set.
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MOPAC Manual (Seventh Edition)
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Semiempirical Methods
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BROCHURE-2011-Web.Pdf
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1 Introduction
VYSOKÉ UČENÍ TECHNICKÉ V BRNĚ BRNO UNIVERSITY OF TECHNOLOGY FAKULTA CHEMICKÁ ÚSTAV CHEMIE MATERIÁLŮ FACULTY OF CHEMISTRY INSTITUTE OF MATERIALS SCIENCE MOLECULAR MODELLING - STRUCTURE AND PROPERTIES OF CARBENE-BASED CATALYST MOLEKULOVÉ MODELOVÁNÍ - STRUKTURA A VLASTNOSTI KATALYZÁTORŮ NA BÁZI KARBENŮ DIPLOMOVÁ PRÁCE MASTER'S THESIS AUTOR PRÁCE Bc. EVA KULOVANÁ AUTHOR VEDOUCÍ PRÁCE RNDr. LUKÁŠ RICHTERA, Ph.D. SUPERVISOR BRNO 2012 Brno University of Technology Faculty of Chemistry Purkyňova 464/118, 61200 Brno 12 Master's thesis Assignment Number of master's thesis: FCH-DIP0639/2011 Academic year: 2011/2012 Institute: Institute of Materials Science Student: Bc. Eva Kulovaná Study programme: Chemistry, Technology and Properties of Materials (N2820) Study field: Chemistry, Technology and Properties of Materials (2808T016) Head of thesis: RNDr. Lukáš Richtera, Ph.D. Supervisors: Title of master's thesis: Molecular modelling - Structure and Properties of carbene-based catalyst Master's thesis assignment: Several models of carbene compounds will be formed using software for molecular modelling. Geometry optimalization and some spectroscopic properties (UV/Vis spectra) will be computed, possibly prediction of RA, IR and NMR spectra will be performed. Data from optimalized structures like bond lengths and angles will be compared with those gained from CCDC (Cambridge Crystallographic Data Centre). Deadline for master's thesis delivery: 11.5.2012 Master's thesis is necessary to deliver to a secreatry of institute in three copies and in an electronic way to a head of master's thesis. This assignment is enclosure of master's thesis. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Bc. Eva Kulovaná RNDr. Lukáš Richtera, Ph.D. prof. RNDr. Josef Jančář, CSc. Student Head of thesis Head of institute - - - - - - - - - - - - - - - - - - - - - - - In Brno, 15.1.2012 prof.
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