Tramonto, an Open-source Code for Modeling Complex Fluids at Interfaces

National Laboratory: 
Sandia National Laboratories
Computational Tools Class: 
Materials Processing

Tramonto is a code developed at SNL to solve classical density functional theories in three dimensions. These theories are used for predicting the structure and properties of fluids at the nanoscale near surfaces. The code currently includes the ability to treat a wide range of physical systems and phenomena, including fluids at interfaces, surface forces, colloidal fluids, polymers and polymer nanocomposites, wetting, porous media, capillary condensation, interfacial phase transitions, self-assembly, lipid bilayers, ion channel proteins, and solvation of surfaces and molecules. The characteristic particle size in DFT models ranges from atoms to colloidal particles and polymers. Tramonto currently solves for the equilibrium, thermodynamic structure and behavior of materials. Relevant to lightweight materials, Tramonto can be used to understand the thermodynamics (phase behavior) of polymer blends and polymer nanocomposites, and the structure of polymeric systems near interfaces. This may be useful in developing general understanding of lightweight, polymer-based composites.

Capability Bounds: 

Tramonto is designed to run on platforms from a desktop machine (Mac or Unix) to massively parallel computers. Calculations run quickly but can require substantial memory for 3D problems.

Unique Aspects: 

Tramonto is the only open-source, three dimensional classical density functional theory code. It builds on Sandia’s Trilinos library for advanced numerical solvers.


Tramonto is open source and available under a GPL license.

Single Point of Contact: 

Name: Amalie Frischknecht, Principal Member of Technical Staff
Phone: (505) 284-8584

  1. M. A. Heroux, A. G. Salinger, and L. J. D. Frink, Parallel segregated Schur complement methods for fluid density functional theories, SIAM J Sci Comput 29, 2059 (2007).
  2. E. S. McGarrity, A. L. Frischknecht, L. J. D. Frink, and M. E. Mackay, Surface-induced first-order transition in athermal polymer-nanoparticle blends, Phys Rev Lett 99, 238302 (2007).
  3. A. L. Frischknecht, M. J. A. Hore, J. Ford, and R. J. Composto, Dispersion of Polymer-Grafted Nanorods in Homopolymer Films: Theory and Experiment, Macromolecules 46, 2856 (2013).
Supporting Document(s): 

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