WebMO Molecule Editor vs V

WebMO allows users to build and view molecules in 3-D, visualize orbitals and symmetry elements, lookup chemical information and properties from external databases, and access state-of-the-art computational chemistry programs. WebMO is recommended for students and faculty in high school, college, and graduate school who desire mobile access to molecular structures, information, and calculations. WebMO capabilities include: - Build molecules by drawing atoms and bonds in a 3-D molecular editor, or by speaking the name (e.g., “aspirin”) - Optimize structures using VSEPR theory or molecular mechanics - View Huckel molecular orbitals, electron density, and electrostatic potential - View molecular vibrations - View point group and symmetry elements of molecules - Lookup basic molecular information, including IUPAC and common names, stoichiometry, molar mass - Lookup chemical data from PubChem and ChemSpider - Lookup experimental and predicted molecular properties from external databases (NIST, Sigma-Aldrich) - Lookup IR, UV-VIS, NMR, and mass spectra from external databases (NIST, SDBS) - Capture high-resolution molecular images - Save and recall molecular structures locally - Export and import structures via email WebMO is also a front-end to WebMO servers (version 14 and higher): - Supports Gaussian, GAMESS, Molpro, MOPAC, NWChem, ORCA, PQS, PSI, Quantum Espresso, VASP, Q-Chem, and Tinker computational chemistry programs - Submit, monitor, and view calculations - View formatted tabular data extracted from output files, as well as raw output - Visualize geometry, partial charges, dipole moment, normal vibrational modes, molecular orbitals, and NMR/IR/UV-VIS spectra

Build and observe to come true with figures of repulsion, geometry, angles. V-SPER, free application, is a support for the teaching of the VSPER theory (Valence Shell Electron Pair Repulsion). This theory makes it possible to predict the geometry of molecules from the sole electrostatic repulsion of valence electron pairs. It is based on the Lewis model of distribution of the valence electrons of the atoms concerned. The latter is a prerequisite to take full advantage of V-SPER. The molecule is denoted AXnEm. The atoms (or portions of molecules) linked to the central atom A are denoted X (n: number of X, whether they are linked by single or multiple bonds). The non-bonding electron pairs belonging to the central atom A and not being involved in bonds are denoted E (m: number of E). V-SPER allows to build simple and 3D objects (molecules) and to display the repulsion figure in blue (FigREP), the molecular geometry in yellow (Geom) as well as the angles. Some angles are just modeled and do not always correspond to experimentally measured angles, such as the relative lengths of single or multiple bonds