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CompuChem Distribution: Gaussian 03 W XP+Vista

Gaussian 03 Windows
jetzt auch als Multiprozessor- Version erhältlich!

Gaussian 03 is the latest in the Gaussian series of electronic structure programs.
Gaussian 03 is used by chemists, chemical engineers, biochemists, physicists and others
for research in established and emerging areas of chemical interest.

New Chemistry Enhanced ONIOM Method. The ONIOM facility in Gaussian 03 has been significantly enhanced over that offered by Gaussian 98 [1-2]: The ONIOM facility [42] now supports electronic embedding for ONIOM(MO:MM) calculations: the electrostatic properties of the MM region can be taken into account during computations on the QM region. ONIOM(MO:MM) optimizations are much faster and can be reliably performed for large molecules (e.g., proteins). The algorithmic improvements include: A quadratic coupled algorithm takes into account the coupling between atoms using internal coordinates (typically, those in the model system) and those in Cartesian coordinates (typically, the atoms only in the MM layer), resulting in more accurate steps. MO/MM optimizations perform micro-iterations for the atoms only in the MM layer between traditional optimization steps on the real system, resulting in faster and more reliable optimizations. Electronic embedding can be combined with micro-iterations. Analytic frequencies are available for ONIOM(MO:MM) calculations, and frequencies for ONIOM(MO:MO) calculations are significantly faster. Gaussian 03 provides support for general molecular mechanics (MM) force fields, including read-in and modified parameters. A standalone MM optimization program is also included. Support for an external program for any ONIOM model (e.g., an external MM program may be used). Solvent Effects The Polarizable Continuum Model (PCM) solvation method has been improved and extended [3-8]: The IEFPCM model [3,9] is now the default, and analytic frequencies are now available for this SCRF method. Additional performance improvements include a new cavity generation technique [10]. Many additional properties can be modeled in solution (discussed later in this brochure). Gaussian 03 can also produce input for Klamt's COSMO-RS program [11], which computes solvation energies, partition coefficients, vapor pressure and other bulk properties via statistical mechanics techniques. Periodic Boundary Conditions (PBC) Gaussian 03 offers PBC calculations for studying periodic systems: e.g., polymers, surfaces and crystals [12-15]. PBC calculations solve the Schrödinger equation subject to the boundary condition that the molecule and the wavefunction repeat indefinitely in one, two or three directions. Hartree-Fock and DFT energies and gradients are available for periodic systems. Molecular Dynamics Dynamics calculations can provide qualitative understanding of reaction mechanisms and quantitative details about the reaction such as product distributions. There are two main approaches to performing these calculations: In Born-Oppenheimer Molecular Dynamics (BOMD), classical trajectories are calculated on a local quadratic approximation to the potential energy surface (for a review, see [16]). Our implementation [17] uses a Hessian-based algorithm for the predictor and corrector steps, an approach which results in a factor of 10 or more improvement in the step size over previous implementations. While it can make use of analytic second derivatives, BOMD is available for all theoretical methods having analytic gradients. Gaussian 03 also offers Atom-Centered Density Matrix Propagation (ADMP) method [18-20] molecular dynamics (available for Hartree-Fock and DFT). Drawing on the work of Car and Parrinello [21], ADMP propagates the electronic degrees of freedom rather than solving the SCF equations at each nuclear geometry. Unlike CP, ADMP propagates the density matrix rather than the MOs. This is much more efficient if an atom-centered basis set is being used. This approach overcomes some limitations inherent in the CP implementation: e.g., there is no need to substitute D for H in order to maintain energy conservation, and both pure and hybrid DFT functionals can be used. ADMP calculations can also be performed in the presence of a solvent [22], and ADMP can be used in ONIOM(MO:MM) calculations. Excited States There are additions and several enhancements to excited states methods: CASSCF calculations are now more efficient due to a new algorithm for evaluating the CI-vector in the full configuration interaction calculation [23]. Practical active spaces increase to about 14 orbitals for energies and gradients (they remain at about 8 orbitals for frequencies). The Restricted Active Space (RAS) SCF method [24] is also available[25]. RASSCF calculations partition the molecular orbitals into five sections: the lowest lying occupieds (considered inactive in the calculation), the RAS1 space of doubly occupied MOs, the RAS2 space containing the most important orbitals for the problem, the RAS3 space of weakly occupied MOs and the remaining unoccupied orbitals (also treated as frozen by the calculation). Thus, the active space in CASSCF calculations is divided into three parts in a RAS calculations, and allowed configurations are defined by specifying the minimum number of electrons that must be present in the RAS1 space and the maximum number that must be in the RAS3 space, in addition to the total number of electrons in the three RAS spaces. NBO orbitals for may be used for defining CAS and RAS active spaces. These provide good initial guesses for the required antibonding orbitals which correlate with the bonds/lone pairs of interest. The Symmetry Adapted Cluster/Configuration Interaction (SAC-CI) method of Nakatsuji and coworkers is now included in Gaussian. This method has many uses: predicting very accurate excited states of organic systems, studying two-to-many electron excitation processes such as the shake-up in the ionization spectrum, and other problem types. For an overview of the SAC-CI method, see [26-27]. Solvent Effects: Excited states can be modeled in the presence of a solvent [28-29] using the CI-Singles and Time Dependent Hartree-Fock and DFT methods. Molecular Properties Gaussian 03 provides many new molecular properties: Spin-spin coupling constants [31-34], which can aid in distinguishing conformations in magnetic spectra. g tensors and other hyperfine spectra tensors [49-52]. Gaussian 03 can produce nuclear electric quadrupole constants, rotational constants, the quartic centrifugal distortion terms, the electronic spin rotation terms, the nuclear spin rotation terms, the dipolar hyperfine terms and Fermi contact terms. All tensors can be exported to Pickett's fitting and spectral analysis program [53]. Harmonic vibration-rotation coupling [43-44]: A spectroscopic property dependent on the coupling between molecules' vibrational and rotational modes. It is used to analyze detailed rotational spectra. Anharmonic vibration and vibration-rotation coupling [44-48]: Using perturbation theory, these higher order terms are incorporated into frequency calculations in order to produce more accurate results. Pre-resonance Raman spectra which yield information about ground state structures, connectivity, and vibrational states. Optical Rotations/Optical Rotary Dispersion: Used to distinguish enantiomers of chiral systems [39-41] (this property is computed via GIAOs). Electronic Circular Dichroism (ECD): This property is the differential absorption in the visible and ultraviolet regions for optically active molecules, and is used to assign absolute configurations [35-36]. Predicted spectra can also be useful in interpreting existing ECD data and peak assignments. Frequency-dependent polarizabilities and hyperpolarizabilities, which can be used to study how the molecular properties of materials vary with wavelength of the incident light [37-38]. Magnetic susceptibilities computed with Gauge-Independent Atomic Orbitals (GIAOs) [30]. This property is the magnetic analogue to the electric polarizability, and it provides insight into the diamagnetic vs. paramagnetic character of molecules. Solvent Effects: Electric and magnetic properties and the various spectra can be predicted for systems in solution as well as ones in the gas phase [54-56]. Properties with ONIOM: The ONIOM method may be used with these electric and magnetic properties. Fundamental Algorithms Much Better Initial Guesses: Gaussian 03 uses the Harris functional for generating initial guesses. This functional [59] is a non-iterative approximation to DFT, and it produces initial guesses which are better than those produced by Gaussian 98: for example, there are modest improvements for organic systems but very substantial improvements for compounds containing metals. New SCF Convergence Algorithm: The default SCF algorithm now uses a combination of two Direct Inversion in the Iterative Subspace (DIIS) extrapolation methods EDIIS and CDIIS. EDIIS [58] uses energies for extrapolation, and it dominates the early iterations of the SCF convergence process. CDIIS, which performs extrapolation based on the commutators of the Fock and density matrices, handles the latter phases of SCF convergence. This new algorithm is very reliable, and previously troublesome SCF convergence cases now almost always converge with the default algorithm. For the few remaining pathological convergence cases, Gaussian 03 offers Fermi broadening and damping in combination with CDIIS (including automatic level shifting). Density Fitting for Pure DFT Calculations: Gaussian 03 provides the density fitting approximation [60,61] for pure DFT calculations. This approach expands the density in a set of atom-centered functions when computing the Coulomb interaction instead of computing all of the two-electron integrals. It provides significant performance gains for pure DFT calculations on medium sized systems too small to take advantage of the linear scaling algorithms without a significant degradation in accuracy. Gaussian 03 can generate an appropriate fitting basis automatically from the AO basis, or you may select one of the built-in fitting sets. Faster and Automated FMM: The fast multipole method (FMM) in Gaussian 98 allowed the computational cost for large DFT calculations to scale linearly with system size. In Gaussian 03, improvements to these algorithms [57] means that their performance gains can be realized for systems of more modest size as well (~100 atoms for pure DFT calculations and ~150 atoms with hybrid functionals). In addition, this feature is now fully automated: the program invokes FMM automatically when appropriate. Coulomb Engine: Gaussian 03 incorporates a faster algorithm for the Coulomb operator for pure DFT calculations. The Coulomb engine produces the exact Coulomb matrix without explicitly forming four center two electron integrals. This substantially reduces the CPU time for the Coulomb problem in pure DFT calculations. O(N) Exact Exchange: A new algorithm for Hartree-Fock and DFT calculations using hybrid functionals implements screening of the exact exchange contribution via the density matrix to eliminate the many zero value terms [62]. This technique results in a linear computational cost for these methods without accuracy loss. Additional Features Additional DFT Functionals: OPTX exchange functional [69]. PBE [70-71] and B95 [72] correlation functionals. VSXC [73], HCTH [74] pure functionals, B1 [72] and variations, B98 [75, 83], B97-1 [76], B97-2 [77], and PBE1PBE [71] hybrid functionals. High Accuracy Energy Methods: G3 and variations [78,79]. The W1 method of Jan Martin [80-81], modified slightly to use the UCCSD method rather than ROCCSD for open shell systems (this method is denoted W1U). Gaussian 03 also includes the related W1BD method, which substitutes the BD method for coupled cluster [84]. This method is both more expensive and more accurate than CBS-QB3 and G3. Douglas-Kroll-Hess scalar relativistic Hamiltonian: This feature allows all electron calculations for heavier atoms (first and second transition rows) when ECPs are not accurate enough [63-66]. For an overview, see [67-68] Gaussian 03 also includes the very large universal Gaussian basis set of de Castro, Jorge and coworkers [82], which approaches the basis set limit. Gaussian W: Molekülberechnungen - Hocheffiziente Geometrieoptimierung, DFT, MP2, MP3, MP4, QCCISD, CSSCF, IR- und Raman-Spektren, NMR (GIAO und GST-Methoden), NMR Shielding Tensors, Onsager, Isodensity und andere Methoden. SCRF Solvation Models, Density Functional Theory u.a. Kompatibel zur Datenübergabe an HyperChem und ChemOffice Ultra ! Some of the Gaussian W Features Electron Structure Theory Advanced algorithms and efficiency innovations for geometry optimizations bring large molecular systems within the reach of electronic structure Methods Fast multiple method and sparse matrix techniques for DFT and frequency calculations. With the ONIOM facility (Morokoma et. al.), which divides a molecular system in up to three "layers" at different accuracy, very lage molecules of biological interest become feasible for study. Molecular Properties NMR-Shielding tensors and chemical shifts at MP2, Hartree-Fock and DFT levels VCD-Intensities at Hartree-Fock and DFT levels Raman-Intensities at Hartree-Fock, DFT and MP2 methods Modeling Excited States ZINDO for large molecules CI-Single Method Time dependent methods (RPA) Solvation Models PCM (polarized continuum model ) now with most up-to-date DPCM, CPCM und IEEPCM facilities (Tomaso et. al.) Other new Features Several DFT-functions Reaction path optimization Handling of ECPs enhanced, Stuttgart/Dresden ECPs incorporated, Midi- Basis set of Trulahr et al., Ahlrichs SVm SVP and TZP and more basis sets... Gaussian 03W can be used to model many properties: Energies using a wide variety of methods, including Hartree-Fock, Density Functional Theory, MP2, Coupled Cluster, and high accuracy methods like G3, CBS-QB3 and W1U.. Geometries of equilibrium structures and transition states (optimized in redundant internal coordinates for speed), including QST2 transition structure searching. Vibrational spectra, including IR, non-resonant and pre-resonance Raman intensities, anharmonic vibrational analysis and vibration-rotation coupling. Magnetic properties, including NMR chem-ical shifts and spin-spin coupling constants. Spectra of chiral molecules: optical rotations, VCD and ROA. G tensors and other contributions to hyper-fine spectra. Gaussian 03W can study compounds and reactions under a wide range of conditions: In the gas phase and in solution. In the solid state, using the Periodic Boundary Conditions facility. Excited states can be studied with several methods: CASSCF and RASSCF, Time Dependent DFT and SAC-CI. The Atom Centered Density Matrix Propagation (ADMP) method can be used to perform molecular dynamics simulations in order to study reaction paths and product state distributions. Recommended Minimum System Requirements Processor: Intel Pentium III, Pentium 4, Celeron, Xeon, or AMD Athlon Operating System: Microsoft Windows XP, Server 2003, Vista (Home Basic, Business and Ultimate) Memory (RAM): 256 MB (512 MB recommended) Disk: 100 MB (G03W storage); and 500 MB or more (scratch space) Other: CD-ROM drive; Mouse New! Multiprocessor and Network/Distributed Parallel Versions The multiprocessor version of G03W is limited to 4 processors (or cores). Similarly, any individual node within a network/distributed parallel job can take advantage of at most 4 processors/cores (e.g., a parallel calculation across 2 dual quad-core computer systems will require 4 workers: 2 per system). Frequently asked questions: Is it possible to run multiple jobs in a queue or is it necessery to enter each job manually? The Windows version of Gaussian has a simple batch system that the user can use to queue up several jobs to run sequentially. On UNIX/Linux systems, the user can use a queuing system, but there is not one included with Gaussian Linux. Is it true, that some calculations run better with the Linux platform compared with a Windows dual core? We use the compilers from the same developers to create both our Windows and IA32 Linux binaries. There are small variations in the performance of Gaussian on these two operating systems (probably due to memory management differences in the operating systems), but the differences are not dramatic. We have not performed extensive testing to determine which types of jobs are most likely affected or if there is a consistent performance advantage to one OS over the other. How much faster is Gaussian Windows on a Quad Core PC- System compared to the single prozessor version? We just took delivery on our first quadcore and don't have real numbers. But based on the performance of the dual cores is should be something like 1.5 * 1.8 or about 2.7 overall. This reflects that the memory bandwidth is shared for each of the dual cores. How can Windows and Unix- Versions of Gaussian cooperate? In short, all utility programs are included in a full G03 distribution, so if G03 and GV are installed on the same computer, nothing else needs to be purchased. Gaussian input files (.com or .gjf), output files (.log or .out) files, and formatted checkpoint files (.fch or .fchk) can be transferred between the platforms without the use of any additional utilities because they are plain text files. Gaussian checkpoint files (.chk) are platform-specific binary files, so one must create a formatted checkpoint file (i.e., a text file) before transferring the formatted file between platforms. In other words, the "formchk" utility program, which is included with Gaussian, must be used on the computer that generated the checkpoint file before the file is transferred. If the customer decides to install GaussViewW on a computer other than the one which has the full G03W program installed, he will need to purchase the G03W Utilities for this computer, or GVW will not be fully functioning. Because the Gaussian Utilities are just a small part of the full Gaussian program, there is no need to purchase both for the same computer. Both the serial and multiprocessor versions of G03W run on 64-bit computers, but as a 32-bit application. Due to compiler limitations, we do not currently have a 64-bit version of Gaussian for Windows. Gaussian W Reference   GaussView Interface