First Official Release

This is the first official release of Excimontec and is the culmination of many years of development and testing. There are no major changes to the underlying code from the last release candidate (v1.0.0-rc.3). The most significant new addition with this release is a comprehensive User Manual that demonstrates the different types of simulation tests that can be performed, explains how the parameter file is manipulated to run different tests, and also details the underlying physical models that are implemented in the code. There has also been some updates to the build system to add clang compiler support and improve automatic compiler detection during installation.

For a detailed listing of all changes, see the Changelog.

This release was primarily developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

Density of States Bugfix

This bugfix release corrects the density of states (DOS) and density of occupied states (DOOS) sampling during the steady state transport test to correctly calculate the DOS and DOOS distribution data with the correct magnitude so that the integral of the DOS is the total density of states and the integral of the DOOS is the total charge carrier density.

For a detailed listing of all changes, see the Changelog.

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

Steady State Charge Transport Test Update

This update provides a major update to the steady state charge transport test:

• Corrected the transport energy calculation algorithm
• Changed transport energy and equilibration energy output to absolute energies that depend on the HOMO energy levels, thereby allowing users test energy shifts in donor-acceptor blends
• Added calculation of transport energy and equilibration energy with and without including the Coulomb potential from the polarons
• Removed previous inaccurate calculation of the Fermi energy
• Added output of the density of states and density of occupied states distribution data with and without including the Coulomb potential from the polarons to allow detailed analysis and accurate calculation of the Fermi energy
• Added output of the steady state current density
• Significantly improved unit tests to help verify accuracy of the steady transport test

For a detailed listing of all changes, see the Changelog.

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

Interfacial Energy Shift, Site Energy Import, and Steady State Transport Test Update

Excimontec v1.0 has left the beta stage and now has a stable feature set and public API.

Major updates in this release:

• Added new interfacial energy shift model for modifying site energies in mixed phases and at interfaces
• Added ability to import custom site energies from a text file
• Added new steady state charge transport simulation feature
• Added Changelog for documenting all changes to the repository
• Significantly increased unit test coverage to help verify functionality and accuracy of the code

For a detailed listing of all changes, see the Changelog.

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

Morphology Import and BKL Algorithm Update

Noteworthy updates in this release:

• Updated README with improved formatting and more specific instructions for building and testing Excimontec and improved formatting
• Updated KMC_Lattice submodule to latest development branch version that has the BKL algorithm implemented and other bugfixes
• Updated BHJ morphology import feature to also allow import of uncompressed morphologies from Ising_OPV v3.2 and v4.0
• Added numerous additional unit tests for electron ToF simulations; triplet exciton lifetime dynamics simulations; triplet exciton diffusion simulations; basic IQE tests for field, temperature, delocalization, and recombination rate dependence of the charge separation yield; and IQE testing at high illumination intensity to check exciton-exciton and exciton-polaron annihilations and bimolecular recombination
• Added many new tests checking for the validity of the input parameters
• Added several tests for importing morphology files from Ising_OPV to check for compression format and file format validity

For a more detailed description of the new changes, see the primary commit changelog

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

Testing and Continuous Integration Update

Noteworthy updates in this release:

• Added the googletest submodule for unit testing
• Added Coveralls integration to monitor test coverage
• Added several code tests of typical usage conditions to probe simulation accuracy
• Added Travis CI integration for continuous integration tests that run build and unit tests with different GCC compilers and MPI implementations
• Updated the default makefile to build the KMC_Lattice library and build a test executable
• Added instructions and scripts for testing the software on your own hardware
• Reorganized the files and directories to keep everything tidy
• Corrected triplet-triplet annihilation mechanism statistics
• Enhanced exciton diffusion test information output
• Improved correlated DOS models and added DOS correlation data output
• Improved time-of-flight charge transport test by adding an initial DOS energy placement option
• Improved options for Coulomb interaction calculations

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

ToF and Dynamics Test Update

Major Updates:

• Added output of mean squared displacement velocity transients during the Dynamics test for calculating the time-dependent exciton diffusion coefficient and charge carrier mobilities
• Corrected several bugs with the current and species density transient data calculated by the ToF and Dynamics tests
• Added API documentation for the Exciton class and all exciton events
• Increased reliability by reducing potential underflow problems

NOTE: This software is still in under development, and as such, there may still be bugs that need to be squashed. Please report any bugs or submit feature requests in the Issues section.

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

Dynamics and IQE Tests Update

Major Updates:

• Significant overhaul of the dynamics test to produce average species density and energy transients from a series of pulses calculated within each processor and between different processors
• Improved tracking of exciton-exciton and exciton-polaron annihilation mechanisms and triplet events and detailed reporting of these various loss mechanisms in the IQE test and dynamics test
• Users can now choose which KMC event recalculation algorithm to use (first reaction, selective recalculation, or full recalculation method)
• Users can now disable charge extraction map output during the IQE and ToF tests to save storage space
• Improved error handling to reduce wasted calculation time and clearly communicate to the user if errors occur and why they occurred

NOTE: This software is still in under development, and as such, there may still be bugs that need to be squashed. Please report any bugs or submit feature requests in the Issues section.

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

First Beta Release!

This version is built with KMC_Lattice v2.0-beta.1 and allows the user to perform several simulation tests relevant for OPV and OLED devices. All major planned features that are to be included in v1.0 are now implemented and have undergone preliminary testing. However, this software tool is still under development, and as such, there may still be bugs that need to be squashed. Please report any bugs or submit feature requests in the Issues section.

Major New Updates:

• Completed rigorous testing and bug fixing of the time-of-flight simulations for neat and bhj morphologies
• Added charge extraction map output when performing time-of-flight and internal quantum efficiency simulations
• Updated morphology import function to handle new morphology file format with Ising_OPV v4
• Corrected major bug in the calculateCoulomb function that calculates electrostatic interactions between charge carriers and electrodes
• Removed the standard namespace from header files to prevent the standard namespace from automatically being applied to all files when including this package as part of a larger software package.
• Reduced simulation status output frequency

NOTE: This software is still in under development, and as such, there may still be bugs that need to be squashed. Please report any bugs or submit feature requests in the Issues section.

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).

Exciton Spin and Correlated Disorder Update

Excimontec is an open-source lattice KMC simulation software package for modeling organic semiconductor materials and devices, such as OPVs, OLEDs, and more. The software is being developed in C++11 and optimized for efficient execution on high performance computing clusters using MPI. This software package uses object-oriented design and extends the KMC_Lattice framework.

This alpha release is built with KMC_Lattice v2.0-alpha.5 and allows the user to perform several simulation tests relevant for OPV and OLED devices. See the README for more information.

Major New Updates in v0.3-alpha:

• Excitons now have a spin parameter to designate them as in either a singlet or triplet state.
• Singlet and triplet excitons have separate lifetimes and hopping rate constants.
• Singlets hop via a FRET mechanism and triplets hop via a Dexter electron exchange mechanism.
• Exciton intersystem and reverse intersystem crossing events dictated by a designated singlet-triplet splitting energy.
• Exciton-exciton and exciton-polaron annihilations events that depend on the spin state of the excitons
• Ability to create a correlated Gaussian density of states with 3 options for correlation functions and a specified characteristic correlation length.
• Improved input parameter file checking.
• Improved performance of exciton and polaron event calculations.

NOTE: This software is still in the alpha phase of development, and as such, there may still be bugs that need to be squashed. Please report any bugs or submit feature requests in the Issues section.

This release was developed under the financial assistance award 70NANB14H012 from U.S. Department of Commerce, National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD).