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CALCULATIONS:

Molecular Mechanics

HyperChem's molecular mechanics methods have many applications to the study of molecular structure and stability. Some typical applications are:

• Calculating relative conformational energies of a series of analogous structures.

• Calculating relative conformational energies of a series of analogous structures.

• Re-optimizing a peptide after introducing a selective mutation.
  Refining structures prior to more rigorous quantum mechanics calculations.
  Assessing possible steric effects in a reactive intermediate.

HyperChem includes four built-in molecular mechanics force fields: new implementations of techniques developed and published by respected research groups.

Semi-Empirical Quantum Mechanics

HyperChem quantum mechanical methods have many practical applications to the study of molecular structure and properties, including:

• Determining frontier orbital interactions between donor and acceptor molecules as illustrated by Diels-Alder cycloaddition reactions.

• Obtaining partial atomic charges, using Mulliken population analysis, to predict likely sites of attack.

• Generating electrostatic potential contour plots to illustrate likely trajectories of approach in drug-receptor docking.

• Calculating unpaired spin densities to identify possible reactive sites on a molecule or for correlation with ESR data.
  

HyperChem includes nine semi-empirical quantum-mechanical methods that are implementations of methods developed and published by respected research groups. These methods range from the simple all-valence-electron method (Extended Hückel) to among the most sophisticated and accurate semi-empirical methods currently available (AM1 and PM3).

Ab Initio Quantum Mechanics

Choose from many commonly used basis sets (STO-1G to D95**) including the standard STO-3G, 3-21G, 6-31G*, and 6-31G** basis sets.  Extra basis functions ( s, p, d, sp, spd ) can be added to individual atoms or to groups of atoms.  Users can also define their own basis sets or modify existing basis sets easily using HyperChem's documented basis set file format. 

Density Functional Theory (DFT) Mechanics

This computational method has been added as a basic computational engine to complement Molecular Mechanics, Semi-Empirical Quantum Mechanics and Ab Initio Quantum Mechanics. This new computational method comes with full capabilities including first and second derivatives so that all the capabilities of other earlier engines are also available with DFT. These include geometry optimization, infrared and optical spectra, molecular dynamics, Monte Carlo, etc.

A full complement of exchange and correlation functions is available, including eight exchange functionals and eight correlation functionals that can be combined in any fashion. Also included are four combination or hybrid functions, such as the popular B3-LYP or Becke-97 methods. A choice of various integration grids, controlling the method’s accuracy, is available to the user.

Read an Overview of HyperChem's features.
Read about HyperChem's Computational Methods. 
Read about HyperChem's stunning visualizations.
Read about HyperChem's other tools for molecular modeling.
Purchase HyperChem 8 Professional.