The unit cells for 1D, 2D and 3D periodic structures based on carbon are shown here, along with displays of multiple cells for the trans-polyvinyl acetate polymer, graphite sheet, and diamond crystal that they model. The dialog to the left illustrates the space group symmetry capabilities the space group for diamond has been selected for this 3D periodic structure. GaussView 6 provides a powerful facility for building such systems and generating their molecule specifications.
Gaussian 16 can perform Periodic Boundary Conditions (PBC) calculations to model periodic systems in condensed phases: i.e., polymers, surfaces and crystals. The view on the right shows the result of using Invert About Atom by clicking on the central carbon atom (indicated with the cursor). The middle view shows this tripeptide species after using Mirror Symmetry. When we click on the hydrogen atom above the left iron atom (with tetrahedral carbon as the current builder fragment), a methyl group is automatically added to all four symmetry-equivalent hydrogen atoms.
We have enabled point group symmetry constraints for this D0h bridged iron complex. The following illustrations depict other advanced building features offered by GaussView 6. Change the value in the angle text box to 90 degrees. Click on the indicated atoms, and make sure that Rotate Groups is selected for both Atom 1 and Atom 4. Click on the hydrogen atom attached to the carbon atom opposite the nitrogen atom to add the second ring.ĥ: The angle between the two rings is wrong, so select the Modify Dihedral icon to twist it back. The structure will regularize.Ĥ: Return to the Ring Fragment panel, and select the benzene ring again. Once you have completed this, hit the Rebond button and then the Clean button. We will demonstrate several of these bulding features by building phenylpyridine:ġ: Select benzene from the Ring Fragment palette, and click inside the View window to add the ring.Ģ: Use the Element Fragment palette to select nitrogen, and replace one of the carbon atoms.ģ: Use the Delete atom tool to remove the hydrogen atom attached to the nitrogen atom. Clean molecular geometries according to rules designed to match chemical intuition.
Symmetrize a structure to a specific point group (raising or lowering its symmetry).Add an atom at the centroid position of a selected group of atoms.Flip the symmetry of a molecule by mirroring or inverting about a selected atom.Changes can be isolated to the desired atom, group or fragment as required. Examine and modify any structural parameter.
Save commonly-used fragments of your own to a custom library. Easily build molecules using a wide range of pre-optimized groups, rings, amino acids and DNA bases.GaussView provides powerful molecule building features, the most important of which are listed below.
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