EosFit is a software suite for calculations involving both thermal expansion and equations of state. The current version is EosFit7.6, which now includes five major components:

EosFit7c: a console program that runs under Windows, Mac-OSX and Linux to manipulate EoS data, fit equations of state and thermal expansion, and to perform EoS calculations, but without graphics. EosFit7c is our development platform. It therefore includes some facilities for more advanced analysis (such as for continuous phase transitions, and strain tensors) than are available in EosFit7 GUI.

EosFit7 GUI: a full-GUI program that runs under Windows, Mac-OSX and Linux. It provides all of the tools needed to visualise and analyse the variations of unit-cell parameter and volume data with pressure and/or temperature. Very useful for teaching and learning about EoS and EoS parameters.

EosFit7 calculator: a GUI to do simple P-V-T calculations for Eos. See the EoS Utilities page.

EosFit7-Pinc: a GUI to do host-inclusion calculations with non-linear elasticity (i.e. proper EoS). See the EoS Utilities page.

cfml_eos: a validated set of Fortran modules that can be ‘used’ (in the Fortran sense) to easily write programs that can read, manipulate and fit EoS data, and perform related calculations for EoS. It was used to write EosFit7-GUI and EosFit-7c. It is available from the CrysFML website.

  • EosFit7 installation packages contain both the console and the GUI programs. Scroll down this page to find the download links and installation instructions!

  • EosFit7-Pinc must be installed seperately. See the EoS Utilities page.

  • EosFit7 available for Mac, Linux and Windows.

The EosFit7 suite of programs was originally developed with the support of ERC grant 307322 to Fabrizio Nestola in the University of Padova, by the SIR project Mile-DeeP of Matteo Alvaro in Pavia, and by Programa de Redes de Excelencia 2015 MAT2015-71070-REDC to Javier Gonzalez-Platas of the Universidad de La Laguna, Tenerife, Spain. Current development continues with the support of ERC starting grant 714936 ‘True Depths’ to Matteo Alvaro in Pavia and Agencia Estatal de Investigacion under the National Program of Sciences and Technological Materials (PID2019-106383GB-C44) to Javier Gonzalez-Platas.

Want to learn more about using EosFit? Come to an EosFit workshop or lecture. Details of planned events are on the teaching page.


EosFit7c is our research and development platform. It has all of the latest algorithms and utilities for manipulating EoS and EoS data. If the EosFit7-GUI cannot do the calculations you need, look at this program.

Latest update: June-2021
New features in this version:

  • More reliable and more precise algorithm for calculating V from P for non-invertible EoS.
  • Kumar PV EoS.
  • Extension of the APL EoS to 4th order.
  • New thermal-pressure EoS based on one Einstein oscillator.
  • q-compromise versions of MGD and Einstein oscillator EoSs.
  • Calculation of heat capacities from parameters of PVT EoS.
  • Improvements in how least-squares refinement is terminated.
  • Crystal system and linear directions can now be specified in eos files.
  • Data scale factors for refinements.
  • CELL utility expanded to handle monoclinic and triclinic cells.
  • Data editing expanded, and consolidated in a new EDIT utility.
  • MPHASE utility to calculate properties of mixtures of phases from their EoS.
  • HOST-INCLUSION utility for anisotropic hosts and inclusions.
  • Improved handling of multiple EoS in one eos file.
  • CLEAR command to delete all data, MODE to set levels of detail in output.

    For full details of all updates in this version, look at the help system after installing the program suite.

  • EosFit7 GUI

    EosFit7 GUI provides:

    • Full graphics support to plot P-V, K-P, K-V, f-F, covariance etc etc.

    • Handling of multiple sub-sets of data. This allows you to easily handle data from phase transitions (see picture), and P-V-T data.

    • Handling and display of several EoS simultaneously....great for teaching EoS theory!!

    • Handling and display of all unit-cell fits simultaneously.

    Latest update: June-2021
    New features in this version:
    • All the new EoS listed under EosFit7c.
    • Improved and faster estimation procedure.
    • Plotting of heat capacities.

    Bug fixes: December 2021
    Some bugs in the graphics library caused the Mac and Linux released versions of the GUI to crash. If you use Mac or Linux, please reinstall the whole EosFit package from the links below.

    Bug fix: August 2023
    The calculator did not work in Windows-11. If you use Windows-11, please reinstall the whole EosFit package from the links below.

    For full details of all updates in this version, look at the help system after installing the program suite.


    The CrysFML subroutine library, which includes the EoS module used to write the EosFit7 programs, is described at www.ill.eu/other_sites/fullprof/php/programs.html.

    It can be downloaded from https://forge.epn-campus.eu/projects/crysfml. The download includes full help documentation for the cfml_eos module.

    EosFit7 Downloads
    • If you have a previous version of EosFit, we recommend that you uninstall it before installing the new version.
    • Choose and download the installation package for your system from the following list.
    • Follow the instructions to do the installation on your computer.
    • If you have problems running the programs after installation, consult the help system.
    7, 8.1, 10 and 11
    • Download a self-installer and run it. This will install the programs, example files, the chm help utility, and desktop short-cuts.
    • You may have to authorise the installation of software 'from an unknown publisher'.
    • Installation may reboot your computer.
    • Start the programs and help system from the short-cuts on your desktop.

    Known problems

    Windows11: The EosFit-calculator in the June 2021 release does not run in Windows-11. The problem is now fixed in this release in August 2023. If you are using Windows-11 please uninstall EosFit7 and then download and install this new version.

    The GUI will only launch the calculator if an EoS is active on the GUI with an Eos Type selected. If the calculator does not launch with an active EoS, go to the Windows control panel and set a system environment variable EOSFIT7 to the name of the folder where you installed the programs (normally C:\program files (x86)\EosFit7).

    Windows7: If you install the program on Windows7 from an account that is not the administrator, you will not get icons on the desktop, and the GUI will not launch the calculator. To fix these problems:
    • Create desktop icons directly from the programs in C:\program files (x86)\EosFit7 by right-clicking and dragging to the desktop.
    • Go to the control panel and set a system environment variable EOSFIT7 to the name of the folder where you installed the programs (normally C:\program files (x86)\EosFit7)

    • EosFit7 can be installed on OS versions higher than 10.9 on 64bit machines.
    • Important: Depending on your security settings you may need to enable installation from unauthorized developers to allow installation of the software.
    • Download a self-installer installer and run it. This will install the program, example files, the help utility, and short-cuts in the application folder. Installation may reboot your computer.
    • To run EosFit7 on a Mac additional software is required. Check if you have v2.7.11 of the XQuartz software installed in your computer. If not, you can download it free of charge from www.xquartz.org and install it following the instructions on the menu. EosFit works with 2.7.11 of XQuartz and may not work with older versions.
    • Start the EosFit7 programs and help system from the short-cuts in the application folder or launchpad.
    • The examples files are installed with the programs under the /Applications folder. If you work in this area, you may not be able to write files from the programs, and the GUI may not launch the calculator. Therefore copy the examples files to a folder under your desktop and always work there.

    Known problems
    • EosFit-GUI from the June 2021 release can crash due to bugs in the graphics library. These are fixed in the current installer. If you installed the original release from June 2021, uninstall it, and re-install the latest version from the download link above.

    • If you try to work under the /Applications folder, several aspects of the programs may not work because they do not have permission to write files. Open a data file under your desktop and then files will be created in that folder without any problems.

    • On some systems the help system cannot be opened directly from EosFit-GUI because of a bug in the graphics library. The help file can be found at: Applications > EosFit7 > html > Eosfit7.html

    • On other operating systems, sometimes the environment variables are not set correctly by the installer. If this happens, you will not be able to launch the calculator from the GUI and/or you will see silly colours for some numbers on the GUI. The section on Mac installation in the help system tells you how to fix these problems.

    • EosFit7 can be installed on any 64bit Linux system.
    • Download 64-bit version and un-pack it (tar -xzvf EoSFit7_Installer_Linux64.tar.gz).
    • Execute the eosfit_setup program to install the EosFit programs.
    • Start the programs and help system directly from the program or program folder.

    Known problems
    • EosFit-GUI from the June 2021 release can crash due to bugs in the graphics library. These are fixed in the current installer. If you installed the original release from June 2021, uninstall it, and re-install the latest version from the download link above.

    • The help system does not work properly in the Firefox browser. The help system does work in Chrome and Chromium, s o we recommend installing one of those and setting it as your default browser.

    If you download and use any of the EosFit programs, please register with us by e-mail. If you use them, please support further developments by referencing the appropriate methodology papers.

    Methodology references
    • EosFit-7c: Angel RJ, Gonzalez-Platas J, Alvaro M (2014) EosFit-7c and a Fortran module (library) for equation of state calculations. Zeitschrift für Kristallographie, 229, 405-419.
      A reprint is also available as a pdf file, Copyright © De Gruyter.

    • EosFit GUI: Gonzalez-Platas J, Alvaro M, Nestola F, Angel RJ (2016) EosFit7-GUI: A new GUI tool for equation of state calculations, analyses. and teaching. Journal of Applied Crystallography, 49, 1377-1382.
      A reprint is also available as a pdf file

    • Fitting of elastic moduli: Milani S, Angel RJ, Scandolo L, Mazzucchelli ML, Boffa-Ballaran T, Klemme S, Domeneghetti MC, Miletich R, Scheidl KS, Alvaro M, Derzsi M, Tokar K, Nestola F (2017) Elastic behaviour of grossular garnet at high pressures and temperatures. American Mineralogist, 102, 851-859.

    • "Isothermal" PVT and MGD EoS: Angel RJ, Alvaro M, Nestola F (2017) 40 years of mineral elasticity: a critical review and a new parameterisation of Equations of State for mantle olivines and diamond inclusions. Physics and Chemistry of Minerals, 45, 95.

    • Fitting of phase transitions: Angel RJ, Alvaro M, Miletich R, Nestola F (2017) A simple and generalised P-T-V EoS for continuous phase transitions, implemented in EosFit and applied to quartz. Contributions to Mineralogy and Petrology, 172,29.

    • Host-inclusion elasticity: Angel RJ, Mazzucchelli ML, Alvaro M, Nimis P, Nestola F (2014) Geobarometry from host-inclusion systems: the role of elastic relaxation. American Mineralogist, 99, 2146-2149.

    • EosFit-Pinc: Angel RJ, Mazzucchelli ML, Alvaro M, Nestola F (2017) EosFit-Pinc: A simple GUI for host-inclusion elastic thermobarometry. American Mineralogist, 102, 1957-1960.

    • Scaling in least-squares refinements: Ehlers AM, Zaffiro G, Angel RJ, Boffa-Ballaran T, Carpenter MA, Alvaro M, Ross NL (2022) Thermoelastic properties of zircon: implications for geothermobarometry. American Mineralogist, 107, 74-81.

    • Calculation of anisotropic inclusions strains in the HostInc utility: Gonzalez JP, Mazzucchelli ML, Angel RJ, Alvaro M (2021) Elastic geobarometry for anisotropic inclusions in anisotropic host minerals: quartz-in-zircon. Journal of Geophysical Research Solid Earth, 126, e2021JB022080.

    • Self-consistent cell parameter calculations and the Cell utility: Angel RJ, Mazzucchelli ML, Gonzalez-Platas J, Alvaro M, F (2021) A self-consistent approach to describe unit-cell parameter and volume variations with pressure and temperature. Journal of Applied Crystallography, 54, 1621-1630.
      A reprint is also available as a pdf file.

    • EoS of mixtures (Mphase utility): Angel RJ, Mazzucchelli ML, Musiyachenko KA, Nestola F, Alvaro M (2023) Elasticity of mixtures and implications for piezobarometry of mixed-phase inclusions. European Journal of Mineralogy, 35, 461-478.

    Some Applications of EosFit

    Molecular materials
    • Allan DR, Bailey D, Bird N, Blake AJ, Champness NR, Huang D, Keane CP, McMaster J, Prior TJ, Tidey JP, Schroeder M (2014) High-pressure studies of palladium and platinum thioether macrocyclic dihalide complexes. Acta Crystallographica B, 70, 469-486. link
    • Budd LE, Ibberson RM, Marshall WG, Parsons S (2015) The effect of temperature and pressure on the crystal structure of piperidine. Chemistry Central Journal, 9, 18. link
    • Madsen SR, Overgaard J, Stalkeb D, Iversen BB (2015) High-pressure single crystal X-ray diffraction study of the linear metal chain compound Co3(dpa)4Br2·CH2Cl2 Dalton Transactions, 44, 9038-9043 link
    • Marshall WG, Urquhart AJ, Oswald IDH (2015) Investigation of methacrylic acid at high pressure using neutron diffraction. Journal of Physical Chemistry B, 119, 12147-12154. link
    • Spencer EC, Soghomonian V, Ross NL (2015) Gallium arsenate dihydrate under pressure: elastic properties, compression mechanism, and hydrogen bonding. Inorganic Chemistry, 54, 7548-7554. link
    • Howie RT, Turnbull R, Binns J, Frost M, Dalladay-Simpson P, Gregoryanz E (2016) Formation of xenon-nitrogen compounds at high pressure. Scientific Reports, 6. link
    • Fedorov AY, Rychkov DA, Losev EA, Zakharov BA, Stare J, Boldyreva EV (2017) Effect of pressure on two polymorphs of tolazamide: why no interconversion? Crystal Engineering Communications, 19:, 2243-2252. link
    • Tailleur E, Marchivie M, Itie JP, Rosa P, Daro N, Guionneau P (2018) Pressure-Induced Spin-Crossover Features at Variable Temperature Revealed by In Situ Synchrotron Powder X-ray Diffraction. Chemistry, 24, 14495-14499. link
    • Giordano N, Afanasjevs S, Beavers CM, Hobday CL, Kamenev KV, O’Bannon EF, Ruiz-Fuertes J, Teat SJ, Valiente R, Parsons S (2019) The Effect of Pressure on Halogen Bonding in 4-Iodobenzonitrile. Molecules, 24. link
    • Giordano N, Beavers CM, Campbell BJ, Eigner V, Gregoryanz E, Marshall WG, Pena-Alvarez M, Teat SJ, Vennari CE, Parsons S (2020) High-pressure polymorphism in pyridine. IUCrJ 7,58-70. link
    • Vervoorts P, Keupp J, Schneemann A, Hobday CL, Daisenberger D, Fischer RA, Schmid R, Kieslich G (2021) Configurational Entropy Driven High-Pressure Behaviour of a Flexible Metal-Organic Framework (MOF). Angewandte Chemie-International Edition 60, 787-793. link

    Physics and Materials Science
    • Bull CL, Playford HY, Knight KS, Marshall WG, Stenning GBG, Smith RI, Hart Z (2015) New insights into the phase diagram of a magnetic perovskite, LaCo1/3Mn2/3O3. Journal of Physics Condensed Matter, 27, 165401. link
    • Errandonea D, Muñoz A, Gonzalez-Platas J (2014) Comment on "High-pressure x-ray diffraction study of YBO3/Eu3+, GdBO3, and EuBO3: Pressure-induced amorphization in GdBO3" [J. Appl. Phys. 115, 043507 (2014)] Journal of Applied Physics, 115, 216101. link
    • Lobanov SS, Zhu Q, Holtgrewe N, Prescher C, Prakapenka VB, Oganov AR, Goncharov AF (2015) Stable magnesium peroxide at high pressure. Nature Scientifc Reports, 5, 13582. link
    • Schaeffer AM, Cai W, Olejnik E, Molaison JJ, Sinogeikin S, dos Santos AM, Deemyad S (2015) Boundaries for martensitic transition of 7Li under pressure. Nature Communications. link
    • Ende M, Effenberger H, Miletich R (2017) Evolution of the alpha-BaMg(CO3)(2) low-temperature superstructure and the tricritical nature of its alpha-beta phase transition. Acta Crystallographica B, 73, 827-835. link
    • Rittman DR, Turner KM, Park S, Fuentes AF, Park C, Ewing RC, Mao WL (2017) Strain engineered pyrochlore at high pressure. Scientific Reports 7, 2236. link
    • Lobanov SS, Dong X, Martirosyan NS, Samtsevich AI, Stevanovic V, Gavryushkin PN, Litasov KD, Greenberg E, Prakapenka VB, Oganov AR, Goncharov AF (2017) Raman spectroscopy and x-ray diffraction of sp(3) CaCO3 at lower mantle pressures. Physical Review B, 96, 104101. link
    • Hwang GC, Blom DA, Vogt T, Lee J, Choi H-J, Shao S, Ma Y, Lee Y (2018) Pressure-driven phase transitions and reduction of dimensionality in 2D silicon nanosheets. Nature Communications, 9, 5412. link
    • Monteseguro V, Sans JA, Cuartero V, Cova F, Abrikosov IA, Olovsson W, Popescu C, Pascarelli S, Garbarino G, Jonsson HJM, Irifune T, Errandonea D (2019) Phase stability and electronic structure of iridium metal at the megabar range Scientific Reports 9, 8940 link
    • Klein RA, Walsh JPS, Clarke SM, Liu ZX, Alp EE, Bi WL, Meng Y, Altman AB, Chow P, Xiao YM, Norman MR, Rondinelli JM, Jacobsen SD, Puggioni D, Freedman DE (2020) Pressure-Induced Collapse of Magnetic Order in Jarosite. Physical Review Letters 125, 077202 link

    Minerals and Geosciences
    • Alvaro M, Nestola F, Ross NL, Domeneghetti MC, Reznitsky L (2014) High-pressure behavior of thiospinel CuCr2S4. American Mineralogist 99, 908-913. link
    • Friedrich A, Winkler B, Morgenroth W, Ruiz-Fuertes J, Koch-Muller M, Rhede D, Milman V (2014) Pressure-induced spin collapse of octahedrally coordinated Fe3+ in Ca3Fe2[SiO4]3 from experiment and theory. Phyiscal Review B, 90, 094105. link
    • Lotti P, Gatta GD, Merlini M, Liermann HP (2015) High-pressure behavior of synthetic mordenite-Na: an in situ single-crystal synchrotron X-ray diffraction study. Zeitschrift fuer Kristallographie, 230, 201-211. link
    • Pippinger T, Miletich R, Merlini M, Lotti P, Schouwink P, Yagi T, Crichton WA, Hanfland M (2015) Puzzling calcite-III dimorphism: crystallography, high-pressure behavior, and pathway of single-crystal transitions. Phyiscs and Chemistry of Minerals, 42, 29-43. link
    • Alvarez-Murga M, Perrillat JP, Le Godec Y, Bergame F, Philippe J, King A, Guignot N, Mezouar M, Hodeau JL (2017) Development of synchrotron X-ray micro-tomography under extreme conditions of pressure and temperature. Journal of Synchrotron Radiation, 24, 240-247. link
    • Siersch NC, Ballaran TB, Uenver-Thiele L, Woodland AB (2017) Compressibility and high-pressure structural behavior of Mg2Fe2O5. American Mineralogist, 102, 845-850. link
    • Miozzi F, Morard G, Antonangeli D, Clark AN, Mezouar M, Dorn C, Rozel A, Fiquet, G (2018) Equation of State of SiC at Extreme Conditions: New Insight Into the Interior of Carbon-Rich Exoplanets. Journal of Geophysical Research - Planets, 123, 2295-2309 link
    • Kong M, Lee Y (2019) Carbonation of Chrysotile under Subduction Conditions. Engineering, 5, 490-497. link
    • Beyer C, Kurnosov AV, Ballaran TB, Frost DJ (2021) High-pressure and high-temperature single-crystal X-ray diffraction of complex garnet solid solutions up to 16 GPa and 823 K. Physics and Chemistry of Minerals, 48, 17. link
    • Stagno V, Bindi L, Takagi S, Kyono A (2021) Can quasicrystals survive in planetary collisions? Progress in Earth and Planetary Science, 8, 27. link