DivCon is a linear scaling semi-empirical program for calculation
of energies, charges and geometries of systems up to ~20,000
atoms. Depending upon the license agreement, available features include:
Linear scaling Divide and Conquer (D&C) calculations[,,].
Cubic scaling standard calculations[,,].
Single point AM1[], PM3[],
PDDG-PM3[], and MNDO[]
calculations.
Geometry Optimization (steepest decent, conjugate gradient, BFGS,
and LBFGS available).
Implicit solvation and Self Consistent Reaction Field (SCRF)
calculations[].
Mulliken[], CM1[],
and CM2[] charge analysis.
Divide and Conquer interaction energy decomposition (PWD)[][]
and SE-COMBINE[].
Nuclear Magnetic Resonance prediction and simulation[].
Quantum mechanics-based scoring function (QMScore)[,].
Parallel processing using MPI[].
The program was initially developed by Steve Dixon. His work included
the development of the semiempirical Divide and Conquer (D&C) algorithm,
implementation of the D&C and standard energy and gradient calculations,
geometry optimization routines, Mulliken charge analysis, cluster
based subsetting strategy and front end of the program. Arjan van
der Vaart added the Particle Mesh Ewald routines, grid based subsetting
routines, extension of the cluster based subsetting schemes, CM1 and
CM2 charge analysis, density matrix build routines, density of state
analysis, frozen density matrix routines, the interaction energy decomposition
routines (serial and parallel), and Talman's algorithm. Valentin Gogonea
added the SCRF routines. Jim Vincent parallelized the single point
energy and geometry optimization routines. Ed Brothers added dipole
and ionization potential routines, the parameterization routines and
the sodium parameters. Dimas Surez added the LBFGS optimization routines,
the transition state routines and the frequency calculation routines.
Ning Liao has added support for a native Poisson-Boltzmann (PB) implementation,
and Andrew Wollocott has added support for restrained minimization.
Subsequently, Hwanho Kim and Lance Westerhoff of QuantumBio Inc. fully
audited, optimized, and modernized much of the source code in order
to impart increased stability and extensibility upon the application.
QuantumBio continues to develop DivCon with these same principles
in mind, and is further refining the parallelization implementation,
adding XML and database support, and integrating the code with QuantumBio's
chemistry platform: CHEMIX.
