HyperChem is a sophisticated molecular modeling environment that is known for its quality, flexibility, and ease of use. Uniting 3D visualization and animation with quantum chemical calculations, molecular mechanics, and dynamics, HyperChem puts more molecular modeling tools at your fingertips than any other Windows program.
What’s new in Version 7.5
Open GL Rendering
The basic rendering modeling in HyperChem has been converted to a full new OpenGL model. This affects all the molecular rendering, giving a generally higher quality of graphics throughout the product.
Image Gallery – click to enlarge
Custom Color Support
It is now possible to color molecules, backgrounds, etc. using any of 16 million available colors rather than the traditional 8 standard colors that HyperChem has used in the past.
Mixed Renderings
The rendering of molecules supports different rendering for different parts of the same molecule. That is any atom can be rendered using any of the rendering molecules — stick, balls, ball and stick, etc.
Tube Rendering of Atoms
A new “tube” rendering is now available for atoms.
Manipulate Protein Structures
Extensive additions have been made to HyperChem’s ability to deal with protein structures. HyperChem now supports four secondary structure descriptions – helices, sheets, turns, and coils. The secondary structures can be individual selected, colored, and rendered using a new secondary structure rendering capability.
Support for Secondary Structure Information in Protein Data Bank files
HyperChem recognizes and supports secondary structure information in its molecule files. Information from protein database (PDB) files is captured for and retained in HIN files. The peptide builder supports this new capability and adds a secondary structure description to all residues.
Protein Secondary Structure Rendering
Secondary structure rendering now includes ribbon lines, narrow ribbon sheets, thick ribbon sheets, encompassing helical cylinders and a coil rendering. These new renderings can be selected for any secondary structure or part of a secondary structure. They can be colored globally or colored differently for specific residues.
Enhanced Protein Builder Capability
In addition to alpha helices and beta sheets, the peptide builder now supports beta turns, parallel and anti-parallel beta sheets, left-handed alpha helices, 310-helices, and pi-helices.
Large Molecule Electron Density Approximation
A rapid new method is available for calculating and displaying the electron density and electrostatic potential of molecules. For example, the new method makes it practical to very quickly display the electron density of large proteins.
Features
Density Functional Package
| Density Functional Theory (DFT) 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. | |
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NMR Simulation
| The HyperNMR package has been integrated into the core of HyperChem. This package allows for the simulation of NMR spectra. An accurante semi-empirical tailored specifically to NMR allows rapid interactive computation of NMR shielding constants (chemical shifts) and coupling constants for molecules as large as proteins. Basedon a solution of the quantum mechanical coupled-Hartree-Fock equations rather than simple database lookup, this package allows full exploration of NMR parameters in any situation, such as a new or novel chemical environment where simple database interpolation is impossible. When appropriate, the NMR parameters can be integrated into a spin Hamiltonian to predict and display the full one-dimensional NMR spectra. The spectra can be manipulated to add line widths so as to simulate experimental spectra.
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Database Package
| A full database capability is integrated into HyperChem 7.5. This includes database search and retrieval of molecules for subsequent molecular modeling calculations as well as the storing of computed properties and optimized structures of your molecules in a new database. Included with the product is a sample database of 10,000 molecules that have previously been optimized with HyperChem. The sample database that is included is representative of common chemical compounds and can be used in a variety of ways associated with research in computational chemistry.
Database retrieval is simple and interactive and a variety of methods can be used to search a database, including a search for 2D or 3D structure. In conjunction with HyperChem’s scripting capability, a generic search based on appropriate computed properties is possible. That is, a question such as, “Give me all molecules whose stored or computed value of X is between x-d and x+d” is possible.
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Charmm Protein Simulations
| The Bio+ force field in HyperChem represents a version of the Chemistry at HARvard using Molecular Mechanics (Charmm) force field. Release 7 of HyperChem updates this force field with new functional terms and new parameters to represent the latest science from the Charmm community. The new parameter sets for Charmm-19 represent new parameters for the bio+ force field of earlier versions of HyperChem, but parameter sets Charmm-22 and beyond represent a newer force field implemented in HyperChem 7 that includes a Urey-Bradley term describing interactions between the two terminal atoms of a 3-atom bond angle. |
Typed Neglect of Differential Overlap (TNDO)
| The Typed Neglect of Differential Overlap method is a new semi-empirical method that merges ideas from molecular mechanics and semi-empirical quantum mechanics. It is designed as a generic semi-empirical method capable of high accuracy when combined with the appropriate parameters. It uses the molecular mechanics idea of atom “typing” to describe the chemical environment of an atom in a molecule with different types being given different parameters. This is the key idea that gives molecular mechanics its validity and accuracy in the absence of any quantum mechanical capability. TNDO combines atom typing a basic quantum mechanical method and allows a rapid semi-empirical method to offer reliable results. The deficiency is the need to develop parameter sets for different types (different classes of molecules) as in molecular mechanics.
HyperChem 7 includes on a first step in this parameter generation but considerable research effort on the part of Hypercube, Inc., HyperChem users, and the general research community is needed to have parameter sets that cover a wide range of chemical situations. Hypercube’s web site will collect these parameter sets. |
Molecules in Magnetic Fields
| It is now possible to explore the structure and reactivity of molecular systems in a uniform magnetic field. HyperChem 6 added an optional external electric field to the workspace and HyperChem 7 adds an optional external magnetic field. The effect of magnetic fields is relatively unknown but this feature allows interactive exploration of how magnetic fields affect chemical behavior. Two terms in the Hamiltonian are included. The first is the interaction of the magnetic field with the orbital angular momentum of electrons and the second is the Zeeman interaction of the magnetic field with the electrons’ spin. This later term is only present with open-shell systems or calculations that use the Unrestricted Hartree-Fock calculations. |
Optimization of the Geometry of Excited States
| A new optimization method, Conjugate Directions, has been added. This method allows geometry optimization using only energies without the necessity of computing gradients (first derivatives). This opens up the possibility of optimizing structures for a number of new situations. In particular, any state of a Configuration Interaction calculation can be optimized. These include excited states for the first time. |
Optimization of MP2 Correlated Geometries
| A relatively accurate and relatively simple way of including electron correlation in ab initio calculations is Moller-Plesset second-order perturbation theory (MP2). Previously, HyperChem users could calculate MP2 energies only but now, using the Conjugate Directions optimizer mentioned above, they can calculate the optimized geometry of a structure using MP2 theory. |
New Rendering of Aromatic Rings
| While HyperChem is fundamentally a molecular modeling program, not a drawing program, it is convenient to have available the ability to easily create annotations of molecular structures and drawings that one can use in presentations. A principal deficiency in this regard has been the lack of a “pretty picture” of aromatic rings since HyperChem represents these with dotted lines, as is convenient for most situations where one is fundamentally interested in modeling not drawing. With HyperChem 7, it is now possible to represent aromatic rings as a more conventional ring with a circle in the middle of it, rather than a ring with dotted bonds. |
Drawing Program
| In the evolution of adding convenient drawing capabilities, as just mentioned, HyperChem 6 added the concept of annotations where text (essentially) could be add to the workspace to annotate chemical structures. These “text” annotations could include many symbols (such as arrows) using various fonts. With HyperChem 7 this drawing capability is extended to lines, ellipses (circles), and rectangles (squares). These elements can be colored, filled or unfilled, dotted, etc.
They are included in the latest HIN file standard so that HyperChem can be used as a simple drawing program. |
Interactive Examination and Manipulation of Parameters
| Molecular mechanics and semi-empirical methods use a large variety of parameters. In particular, the new TNDO method lends itself to a variety of parameter sets for a variety of different chemical computations. It has always been possible to edit the text-based parameter files and re-compile them. With HyperChem 7, it is possible to see parameters on-screen associated with selected atoms, bonds, torsions, etc. These can then be immediately edited if desired. In addition, it is possible, interactively, to copy whole parameter sets making it feasible to interactively explore different parameters sets in an easy fashion. |
Enhanced Polymer Builder
| The polymer builder has been enhanced to create branched polymers as well as linear polymers. As TAIL is attached to HEAD, it is possible to specify random attachment to either the new HEAD or an old HEAD, creating a branch in the polymer. In addition to explicitly specifying torsion angles for the HEAD to TAIL join, it is now possible to specify torsion angles for the internal backbone of the monomer; specifically, one can have these monomer backbone angles chosen randomly or as originally specified in describing the monomer. |
New Basis Sets
| In conjunction with the new DFT capability of HyperChem 7, a large number of new basis sets have been added to the sets already included with HyperChem. These basis sets are available for either the ab initio module or the DFT module. |
Feature summary
Structure Input and Manipulation
Building molecules with HyperChem is simple: just choose an element from the periodic table, and click and drag with the mouse to sketch a structure. Mouse control of rotation around bonds, stereochemistry, and “rubber banding” of bonds makes changing structures easy. Extensive selection, highlighting, and display capabilities make it easy to focus on areas of interest in complex molecules.
- Select, rotate, translate, and resize structures with convenient mouse controlled tools. Modify settings to control operation of tools.
- Convert rough sketches into 3D structures with HyperChem’s model builder.
- Apply builder constraints easily: specify bond lengths, bond angles, torsion angles, or the bonding geometry about a selected atom.
- Specify atom type, atom charge, formal charge and atomic mass.
- Build clusters and complex molecular assemblies; move individual atoms and molecules as easily as you move groups.
- Build peptides and nucleic acids from amino acid and nucleotide residue libraries.
- Mutate residues and build large molecules incrementally (make changes at any point).
- Add a periodic box of pre-equilibrated water molecules for aqueous solvation studies. Periodic boundary conditions can be used with other solvent systems, or without solvents.
- Import structures from standard file formats: Brookhaven PDB, ChemDraw CHM, MOPAC Z-matrix, MDL MOL and ISIS Sketch, and Tripos MOL2 files.
Molecular Display
- Display structures using ball and stick, fused CPK spheres, sticks, van der Waals dots, and sticks with vdW dots; switch easily between rendering styles.
- Specify shading and highlighting, stick width, and the radii of spheres. Stereo and perspective viewing are also available.
- Display a Ray Traced image of the molecules in the workspace.
- Select and name sets of atoms for custom display or monitoring of properties.
- Set and display custom labels for atoms.
- Display bond labels showing the current bond length or the currently computed quantum mechanical bond order.
- Display protein backbones using ribbons, with optional display of sidechains.
- Highlight potential hydrogen bond interactions.
- Display dipole moment vectors and gradient vectors.
Computational Chemistry
Use HyperChem to explore quantum or classical model potential energy surfaces with single point, geometry optimization, or transition state search calculations. Include the effects of thermal motion with molecular dynamics, Langevin dynamics or Metropolis Monte Carlo simulations. User defined structural restraints may be added.
Types of Calculations
- Single point calculations determine the molecular energy and properties for a given fixed geometry.
- Geometry optimization calculations employ energy minimization algorithms to locate stable structures. Five minimization algorithms are provided.
- Vibrational frequency calculations find the normal vibrational modes of an optimized structure. The vibrational spectrum can be displayed and the vibrational motions associated with specific transitions can be animated.
- Transition state searching locates the metastable structures corresponding to transition states using either Eigenvector Following or Synchronous Transit methods. Molecular properties are then calculated.
- Molecular dynamics simulations compute classical trajectories for molecular systems. Quantum forces can be used to model reactive collisions. Heating, equilibration, and cooling periods can be employed for simulated annealing and for studies of other temperature dependent processes. Both constant energy and constant temperature simulations are available.
- Langevin dynamics simulations add frictional and stochastic forces to conventional molecular dynamics to model solvent collisional effects without inclusion of explicit solvent molecules.
- Metropolis Monte Carlo simulations sample configurations from a statistical ensemble at a given temperature and are useful for exploring the possible configurations of a system as well as for computing temperature dependent equilibrium averages.
Computational Methods
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.
Semi-empirical Quantum Mechanics
- HyperChem offers ten semi-empirical molecular orbital methods, with options for organic and main-group compounds, for transition metal complexes, and for spectral simulation.
- Choose from Extended Huckel, CNDO, INDO, MINDO/3, MNDO, MNDO/d, AM1, PM3 (including transition metals), ZINDO/1 and ZINDO/S.
Molecular Mechanics
- Four force fields provide computationally convenient methods for exploring the stability and dynamics of molecular systems.
- Added flexibility of user defined atom types and parameters.
- Choose from MM+, a general purpose force field, and three specialized biomolecule force fields: Amber, BIO+, and OPLS.
Mixed Mode Calculations
- HyperChem allows you to perform quantum calculations on part of a molecular system, such as the solute, while treating the rest of the system classically. This boundary technique is available for all the quantum methods, with some limits for ab initio calculations.
Customize and Extend HyperChem with the Chemist’s Developer Kit
- Streamline HyperChem’s menus. Add new graphical and computational features; create custom menus for specific applications.
- Interface to Visual Basic, C, C++ and FORTRAN programs. Add dialog boxes as well as menu items. For example, you could use HyperChem for visualization of structures and results from non-graphical quantum chemistry programs.
- Link HyperChem procedures to other Windows programs such as MS Word and Excel; direct selected results to these applications for convenient analysis and reporting.
Results with HyperChemDisplay
Customize and Automate
Interface and Extend
Predict
Save Results
Integrated Modules RAYTRACE The Raytrace module enables you to create stunning raytraced images of molecules in the workspace by bridging with the very high-level graphics visualization application known as Persistence of Vision (POV) Ray for Windows.
RMS Fit RMS Fit provides a new tool for comparing structures of molecules in HyperChem, augmenting the existing overlay function and the flexible fitting provided by restrained optimizations. The RMS Fit module lets you carry out the following tasks:
SEQUENCE EDITOR Sequence Editor provides additional tools for manipulating strings of amino acids in HyperChem. The Sequence Editor brings the following capabilities to HyperChem:
CRYSTAL BUILDER With Crystal Builder you can build up crystals in HyperChem by hand, by entering fractional coordinates, or choose from a set of samples provided. Crystal Builder gives you control over the face you view, and the size of the crystal you build; it also allows you to read Cambridge Crystal Database files into HyperChem. The Crystal Builder includes the following features:
SUGAR BUILDER With Sugar Builder you can construct polysaccharides from individual saccharide components. The Sugar Builder’s features include the following:
CONFORMATIONAL SEARCH The Conformational Search module is a tool for finding and saving stable structures of molecules, using stochastic approaches based on modification of torsion angles. Conformational Search has a wide range of options to tune the search for your particular needs. The general approach is to twist selected torsion angles of the system to distort a structure and, if certain tests are met, optimize to obtain a new candidate structure. The new structure can be accepted or rejected as a structure of interest according to a variety of criteria. Here is a list of some of the more important facilities of Conformational Search:
QSAR PROPERTIES QSAR Properties allows calculation and estimation of a variety of molecular descriptors commonly used in Quantitative Structure Activity Relationship (QSAR) studies. Most of the methods were developed for and are primarily applicable to organic molecules. Here are some of the properties you can estimate using QSAR Properties:
SCRIPT EDITOR HyperChem’s scripting capability is one of its most versatile features, allowing it to be controlled from outside using scripts or external programs. The Script Editor is a tool to assist you in developing scripts in the HyperChem language, and to send script messages directly to HyperChem as a command line. Script Editor’s features include the following:
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New Force Fields
HyperChem added significant new capability to the AMBER method of molecular mechanics by including up-to-date modifications of this force field. AMBER code supports 5 parameter sets with their associated functional forms:
- Amber 2
- Amber 3
- Amber for saccharides
- Amber 94
- Amber 96
- Amber 99
Default Parameter Scheme for AMBER and OPLS
Any AMBER or OPLS computation can continue computing with default parameters, when explicit parameters are missing from the relevant parameter file. The normal AMBER and OPLS parameter scheme fails when explicit parameters associated with “atom types” are not available. with default parameters, no calculation fails for lack of parameters.
ESR Spectra
Calculated values of Hyperfine Coupling constants are also available, for characterizing the ESR spectra of open shell systems.
Electric Polarizabilities
Computation of polarizability tensors is available.
Plots of Potential Energy
You can select one or two structural features (bond length, torsion angle etc.) and request a plot of the potential energy as a function of either a single structural feature (2D plot) or two structural features (3D plot).
Protein Design
You can cut and paste any amino acid sequence. That is, a piece can be cut out, a piece inserted, or a sequence of one length replaced by a new sequence of a different length. Annealing operations are, of course, required for the rest of the protein to adapt to these modifications.
Electric Fields
It is possible to superimpose an applied electric field on any calculation. For example, a charged system will now drift in the workspace during a molecular dynamics run if an external electric field has been applied. Studying molecular behavior in an electric field is now possible.
Annotations
While it has always been possible to copy the rendering of molecules in HyperChem into a file or onto the clipboard and then transfer the rendering into a drawing or painting program to prepare overhead transparencies or other presentation material, directly creating such material without leaving HyperChem is now possible.
An annotation in HyperChem is a length of text that can be placed anywhere in the workspace. Because the text can have attributes such as a font, a color, and a size, it is possible to create annotations such as arrows, lines, circles, rectangles and any number of other drawing primitives. Annotating the molecules that are being modeled in HyperChem allows you to print the workspace and more easily describe to others the results of your modeling.
HyperChem contains a number of features associated with creating and manipulating these annotations. Because they exist in a plane or layer that is independent of the molecular or modeling plane, they augment rather than collide with the modeling of earlier versions of HyperChem. At the same time by being able to show or print both planes at the same time, a rich set of annotation options is possible.
While that is not the primary intent, HyperChem could now be used to prepare illustrations independent of chemistry and molecular modeling.
Charge and Multiplicity are Saved
The total charge and spin multiplicity are now stored in the HIN file and are restored when a molecular HIN file is read. Earlier, these had to be set interactively for any new molecule in the workspace.
Drawing Constraints
It is now possible to constrain your drawing of 2D molecules so that the the resultant drawn molecule has uniform bond lengths and angles and resembles a standard 2D molecular representation as might be seen in textbooks. These constraints have no effect on the subsequent 2D to 3D model building.
Graphical Display of Gradients
It is possible to visualize the gradient (force) on any atom as a vector. Any set of atoms can display these vectors.
Bond Labels
A set of dynamically updated labels are available for bonds as well as atoms and residues. These bond labels can be one of:
- Bond length
- Bond order – as calculated quantum mechanically
Enhanced Selection Capability
HyperChem operations depend to a great extent on one’s ability to select a subset of atoms. For example, it is possible to select atoms based on the range of various computed quantities such as their atomic charge or atomic gradient. Thus, for example, one can now select all atoms with a charge between -0.1 and 0.1.
The atom selection options are organized as either a selection based on a “string” property of an atom, such as the atom type (e.g. CH), or a “number” property such as the atom charge described above.
Whether you use HyperChem’s many internal features or build a live link with your other chemistry programs, the benefit of working with HyperChem Release 7 is that you are free to focus on the things that you do best. HyperChem does the rest.