Introduction

PSCF is a numerical implementation of the Edwards-Helfand self-consistent field theory (SCFT) for periodic phases formed by liquids containing block copolymers. It is designed to describe spatially periodic structures of incompessible liquids that may contain a mixture of block copolymers, homopolymers, and small molecule solvents. It can describe structures with 1, 2, 3 or dimensional periodicity with any type of unit cell and any specified space group symmetry. The modified diffusion equation (MDE) is solved with an efficient pseudo-spectral method. The code was designed primarily for calculating phase diagrams of block copolymer melts by comparing free energies of competing ordered phases, and contains several features that facilitate such calculations.

Features

  • Arbitrary mixtures of block copolymers, homopolymers, and solvents
  • Ordered phases with 1, 2, or 3 dimensional periodicity
  • Canonical and grand-canonical ensembles
  • Arbitrary 2 or 3D unit cell, with non-orthogonal axes
  • Imposition of any specified space-group symmetry
  • Hard-coded “database” of all 230 3D space groups and 17 2D plane groups
  • Variable unit cell algorithm, in which unit cell parameters adjust to minimize free energy
  • Continuation of solutions along lines in parameter space
  • Linear response calculations for periodic structures

Documentation

The developer manual is available online via a link from the program home page, and can also can be regenerated from the source code (see the file doc/README for instructions).

Dependencies

The program is written in Fortran 90. It depends the open source FFTW Fast Fourier Transform library and the LAPACK linear algebra library. To compile the code from source, you will thus need a Fortran 90 compiler and these two libraries.

Contributors

  • David Morse
  • Chris Tyler
  • Jian Qin
  • Amit Ranjan
  • Raghuram Thiagarajan
  • Akash Arora