A pro­gram for mol­e­c­u­lar data visu­al­iza­tion, mol­e­c­u­lar con­struc­tion, and ther­mo­dy­nam­ic cal­cu­la­tions

(Last update: 09.10.2015)

Moltran is a pro­gram for inspec­tion of results after quan­tum chem­i­cal cal­cu­la­tions per­formed with dif­fer­ent quan­tum chem­i­cal pack­ages includ­ing Gauss­ian, GAMESS, Priro­da, CFOUR and oth­ers. It allows edit­ing the mol­e­c­u­lar struc­tures work­ing as a mol­e­c­u­lar builder. Dur­ing the mol­e­c­u­lar edit­ing, you can save or retrieve the mol­e­c­u­lar frag­ments to a data­base and use them lat­er to cre­ate more com­pli­cat­ed struc­tures. A spe­cial fea­ture of MOLTRAN is a pos­si­bil­i­ty to per­form var­i­ous ther­mo­dy­nam­i­cal cal­cu­la­tions (with a broad vari­a­tion of mod­el para­me­ters) and tak­ing into account the inter­nal rota­tions if they are present in the mol­e­cule. Have a look at the Moltran screen­shots (sam­ple data files cre­at­ing the screen­shots can also be found here).

Moltran Man­u­al

Ther­mo­dy­nam­ic cal­cu­la­tions with Moltran

Down­load Moltran for Win7/Win8 - MOLTRAN v.2.5 (build 2155) for Win­dows7 / Win­dows8 with graph­ic inter­face. Gaus­sian09, GAMESS-US, PC GAMESS, Priro­da8, and CFOUR (par­tial­ly) for­mats are sup­port­ed. Note: Due to the extra secu­ri­ty rules of Windows7/8 applied to “c:\Program Files(x86)” direc­to­ry, it is rec­om­mend­ed to install the pro­gram to oth­er fold­er (say, c:\Moltran). Oth­er­wise, prob­lems with frag­ments data­base can appear.

Down­load Moltran for WinXP - MOLTRAN v.2.5 (build 1680) for Win­dowsXP with graph­ic inter­face (MoltranSetup.exe, zipped to avoid the serv­er restric­tions, Short man­u­al and UnIn­staller are includ­ed). Sta­ble on Win­dows 2000, XP, Vista. Gaus­sian09 for­mat is now sup­port­ed.

Moltran for Lin­ux — exper­i­men­tal release of build 1373 w/o graph­ics inter­face — only for TD cal­cu­la­tions. Com­piled with Intel For­tran 10.1 under Open­Suse 10.3 (Intel+AMD plat­forms). Instal­la­tion instruc­tion (install_unix.txt) inside the zip-archive (

New fea­tures in the cur­rent ver­sion

  • Auto­mat­ic Recog­ni­tion of Inter­nal Rota­tions (ARIR)
  • Improved ther­mo­dy­nam­ic cal­cu­la­tions with inter­nal rota­tions
  • Auto­mat­ic recog­ni­tion of sym­me­try group and rota­tion sym­me­try num­ber
  • Semi­em­pir­i­cal opti­miza­tions
  • Improved oper­a­tions with frag­ment library
  • Improved cal­cu­la­tions with­in the Pitzer-Gwinn approx­i­ma­tion (direct cal­cu­la­tion of reduced mass matrix)
  • Monte Car­lo cal­cu­la­tion for the TD func­tions of inter­nal rota­tions
  • Cur­rent­ly Moltran sup­port the fol­low­ing data file for­mats:
    • Gaus­sian09 out­put (auto­mat­ic recog­ni­tion)
    • Gaus­sian03 out­put (auto­mat­ic recog­ni­tion)
    • Gaus­sian94 out­put (auto­mat­ic recog­ni­tion)
    • Gauss­ian z-matrix input (/gz<skip lines> com­mand line key­word)
    • Gauss­ian Carte­sian matrix input (/x<skip lines> com­mand line key­word)
    • PC GAMESS v.6 and high­er out­put (auto­mat­ic recog­ni­tion)
    • GAMESS US (auto­mat­ic recog­ni­tion)
    • Priro­da v.8 and high­er
    • CFOUR v.1 and high­er
    • Var­i­ous XYZ file for­mats (/nxyz<skip lines>, /dnxyz<>, /ndxyz<>
    • Any files with NXYZ matri­ces with search the matrix by label (/nxyzs<skip lines>@<label>)

Kin­Tran is a pro­gram plug-in for Moltran for cal­cu­la­tions of the reac­tion ther­mo­dy­nam­ics and kinet­ic con­stants of ele­men­tary reac­tions.

MOLTRAN cita­tion. If you pub­lish the results obtained with Moltran please ref­er­ence it as fol­lows:

S.K. Igna­tov, Moltran v.2.5 — Pro­gram for mol­e­c­u­lar visu­al­iza­tion and ther­mo­dy­nam­ic cal­cu­la­tions , Uni­ver­si­ty of Nizh­ny Nov­gorod, 2004,

Please send your com­ments on Moltran to: