TIGER

Other Resources: 9 results
Dependence of S on Molecular Structure  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Molecular Mechanics / Dynamics
Some Trends In Entropy Values  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Molecular Mechanics / Dynamics
Microscopic View of Chemical Reactions  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Molecular Mechanics / Dynamics
Termolecular Processes  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Molecular Mechanics / Dynamics
Mol4D: A Web-Based Computational Chemistry Interface for Educational Purposes  Oliver Stueker, Ingo Brunberg, Gregor Fels, Hens Borkent, Jack van Rooij
Mol4D (Molecules in Four Dimensions) is a web and Chime based molecule editor and computational interface. Visualization and interactivity are the predominant features. Computational results, based on MOPAC, are obtained within seconds and structures presented using the Chime plug in. Orbital information (in VRML format) and the selection of parameters for a linear or grid scan are options.
Computational Chemistry |
Molecular Modeling |
Molecular Mechanics / Dynamics
Moth Repellent Chemicals  William F. Coleman
The featured molecules this month come from the paper The chemistry of moth repellents by Gabriel Pinto. Several of the molecules exhibit interesting structural features that students should explore. Hexachloroethane, not surprisingly, has energy minima in the staggered form that is shown. Students could be asked to look at the models for empenthrin and permethrin to see if they can see similar staggered arrangements in these more complex molecules. Camphor is a good way to introduce strained structures, and students can use the Jmol version of the model to measure bond angles to see if they can identify some of the consequences of this strain. The carbonyl moiety in camphor is interesting as it is non-planar.
Molecular Properties / Structure |
Molecular Mechanics / Dynamics
Molecular Model of trans-3-(9-Anthryl)-2-Propenoic Acid Ethyl Ester  William F. Coleman
The Featured Molecules this month come from the paper by Nguyen and Weisman on solvent-free Wittig reactions and the stereochemical consequences of crowding in the transition state. The molecules include those pictured in the paper as well as the cis-isomer of 3-(9-anthryl)-2-propenoic acid ethyl ester. All structures were optimized at the B3LPY/6-31G* level. In the case of ethyl cinnamate, the cis-isomer is slightly more stable thermodynamically than the trans isomer, lending further support for the argument that the observed product distribution arises from the energetics of the transition state.
Molecular Modeling |
Molecular Modeling |
Molecular Mechanics / Dynamics
Web-Based Interactive Animation of Organic Reactions  Ingo Brunberg, Gregor Fels, Hens Borkent, Jack van Rooij, Oliver Stueke
This WWW-based service for the automated animation of organic reactions we believe to be a versatile tool for teaching and learning organic chemistry. It allows the investigation of the influence of substituents of starting materials on the reaction coordinate and the energy of the depicted reaction. Starting from a list of precalculated organic reactions hydrogen atoms can be substituted by a variety of organic substituents and functional groups using the molecule editor. The new set of starting material is submitted to the calculation of intrinsic reaction coordinates that yields automatically an animation of the reaction that can be viewed with the Chime plugin.
Computational Chemistry |
Molecular Modeling |
Molecular Mechanics / Dynamics |
Enrichment / Review Materials
Mechanisms That Interchange Axial and Equatorial Atoms in Fluxional Processes  Marion E. Cass, Henry S. Rzepa, King Kuok Hii
The Berry pseudorotation is a classical mechanism for interchanging axial and equatorial ligands in molecules with trigonal bipyramidal geometry. Teaching this mechanism presents particular pedagogic problems due to both its dynamic and three dimensional character. The approach taken here illustrates these processes using interactive animations embedded in a Web page and overcomes many limitations of a printed page.
Computational Chemistry |
Molecular Properties / Structure |
Nonmetals |
Enantiomers |
NMR Spectroscopy |
Mechanisms of Reactions |
Molecular Mechanics / Dynamics