Cepos Mopac 6  

Pricing Structure

EMPIRE™ is sold as single-seat or site license for the single node versions or as site license for the multi node versions.

Industrial Licenses
Industrial licenses include full support, maintenance and upgrades.

Academic Licenses
Free academic licenses do not include support or upgrades.
Academic site licenses are available for only € 250.
Academic sales are only possible via Internet or by Fax.

Pricing Guide

EMPIRE™ and EH5cube™


EMPIRE™ is a modern, parallel (but not linear scaling) semiempirical molecular orbital program that can treat extremely large systems (it has been tested up to 100,000 atoms for non-periodic calculations and for repeat units in periodic calculations up to 50,000 atoms). EMPIRE™ scales well up to thousands of cores, depending on the size of the system. There is no software-imposed upper limit to the size of the systems that can be calculated.
EMPIRE is particularly interesting for materials science because it can calculate extensive crystalline systems with defects or dopants, amorphous systems (by using very large repeat units), 2D electronic devices and self-organized aggregates. Because it does not use any local approximations, EMPIRE™ is particularly suitable for electroactive systems.
In biology and medicinal chemistry, EMPIRE™ serves as the compute engine for quantum-mechanical-based computer-aided drug design or to investigate the properties of entire proteins, for instance for electron-transfer in redox-active proteins.
For simulations of soft matter, EMPIRE™ is often used to perform single-point calculations on snapshots taken from classical molecular-dynamics simulations within an ensemble model.
EMPIRE™ currently offers the MNDO, MNDO/D, AM1, PM3, PM6, RM1, hpCADD and MNDO-F Hamiltonians. All EMPIRE™ parameter files are in an easily readable ASCII format and include all necessary information to characterize the Hamiltonian completely. EMPIRE™ calculations are thus completely transparent and custom Hamiltonians can be implemented easily by the user.
EMPIRE19™ includes both extensions of the functionality and performance enhancements compared to its predecessor:

  • Improved performance: Among other performance enhancements, the calculation of gradients has been speeded up significantly. This improvement speeds up geometry optimizations and numerical calculations of the normal vibrations, especially for periodic systems, where the improvement is largest.
  • Normal vibrations: EMPIRE19™ can now calculate normal vibrations (frequencies and eigenvectors) using a finite-difference numerical approach.
  • New Hamiltonians: The following new Hamiltonians have been implemented
    • PM6 – Stewart’s most popular Hamiltonian
    • RM1 – an improved parameterization of AM1
    • hpCADD – a dedicated Hamiltonian for calculating properties such as the molecular electrostatic potential. hpCADD is only suitable for single-point calculations
    • MNDO-F – MNDO extended with the new self-consistent, multi-center, anisotropic “Feynman” dispersion correction

Excited states: EMPIRE19™ includes configuration-interaction (CI) calculations for excited states and band gaps of non-periodic systems. Both standard CI and UNO-CI are available. CI calculations for periodic systems are being implemented.

Free academic version of EMPIRE™

Annual single-seat licenses for the single-node version of EMPIRE™ are freely available for bona fide academic users. To register and download the program, please click here.


EH5cube™ is the postprocessor for EMPIRE™ calculations. EMPIRE™ writes a small ASCII output file that contains only the most important information. It’s primary (and most detailed) output is a binary wavefunction file in the platform-independent HDF5 format. It is possible to recreate essentially all electronic properties of the molecule or periodic system from the information contained in the .h5 file. EH5cube™ reads the .h5 file and creates, for instance, Gaussian cube files containing the electron density, molecular orbitals or local properties (local ionization energy, local electron affinity or local polarization), either on a grid or at points in space specified in the program input.


A customizable and entirely web-based molecular modeling system including single-node EMPIRE19™ ...more (visit the product side)