This directory contains a collection of examples of input files that can be run with the PSCF polymer self-consistent field theory software to compute structure and free energies for periodic microostructures of block copolymer melts or mixtures that contain block copolymers. The examples are provided as examples of the file formats and input file syntax, and as potentially useful starting points for constructing new simulations.

The home page for PSCF, which provides links to the source code, documentation, and binary packages for a few operating systems, is located at

 http:https://research.cems.umn.edu/morse/code/pscf/home.php

The source code for PSCF is provided in a separate github repository at

 https://github.com/dmorse/pscf.

I. Directory Structure

The top level subdirectories of this repostiory each contain a tree of examples of simulations involving different types of system. The main subdirectories are currently:

diblock/ triblock/ solution/

Directory diblock/ contains examples for neat (one-component diblock) diblock copolymer melts. Directory triblock/ contains examples for ABC triblock terpolymer melts. Directory ssolution/ contains examples of ordered phases of a mixture of diblock/ copolymer and selective molecules solvent. We will refer to these top level subdirectories in what follows as "system level" directories.

The subdirectories of these system level directoires each contain simulations of a different possible phase (i.e., crystal structure) of the system of interest. The names of these subdirectories are abbreviations of the names of the phases: lam for lamellar, hex for hexagonally packed cylinders, gyr for gyroid, etc. Each system level subdirectory contains a CONTENTS file explaining these abbrevations in greater detail.

Directories that contain simulations of a particular phase may either contain either the input files for a single example, or subdirectories containing several examples. When such a directories contain two subdirectories named iterate/ and sweep/, the iterate/ directory contains an example of a simulation that solves the SCF equations for a single set of parameters, and the sweep/ directory contains an example that uses the SWEEP parameter file command to perform a series of simulations along a line in parameter space.

II. Input Files

In what follows, we refer to a directory that contains the input files for a single example or several examples that use the same input omega file as an example directory.

In each example directory, there are two types of input files, named

  param*   = parameter files
  in.omega = input omega (chemical potential) field

Each example file contains only one input omega file, but some may contain one or more param files. In example directories that contain more than one parameter files, the simplest example is usually named simply 'param'.

Almost all example directories contains an initially empty subdirectory named 'out/'. This is where output files will be placed when you run the example.

III. Running an an example:

To run an example:

1) Change directory (cd) into the example directory of interest.

2) Enter the command

   pscf < paramfile

where paramfile denotes the name of a particular parameter
file.  This command will run the example while outputting 
information reporting the progress of the calculation to 
the screen. Alternatively, the command

   pscf < paramfile > out/log &

will run the example in the background and output this 
information to a file named "log" in the out/ sub-directory.

IV. Output files

ITERATE Examples:

Examples that solve the SCFT equations for a single set of input parameters create the following output files:

  out/out   = output summary 
  out/rho   = output monomer volume fraction fields
  out/omega = output omega fields

SWEEP Examples:

Examples in which the parameter file contains a SWEEP command cause the program to solve the SCF equations for a set of input parameters along a line in parameter space. The SWEEP command can specify any line along which one or more of the parameters are incremented in uniform increments, with increment values that are specified in the input script. The output files produced by running a SWEEP example are also placed in the out subdirectory, and have names of the form

  out/$(N)out     = output summary fields
  out/$(N)rho     = output density fields
  out/$(N)omega   = output omega fields

where $(N) takes on integer values 0, 1, 2, etc. That is, the directory will contain output summary files out/0.out, out/1.out, etc. and a similar sequence of number rho (volume fraction) files named out/0.rho, out/1.rho, etc, and numbered output chemical potential files named out/0.omega, out/1.omega, etc.