The kernel of the Dalton suite is the two powerful molecular electronic structure programs, Dalton and LSDalton.

Together, the two programs provide an extensive functionality for the calculations of molecular properties at the HF, DFT, MCSCF, and CC levels of theory. Many of these properties are only available in the Dalton suite.

The history of the Dalton program suite

The history of Dalton starts in fall of 1983, when Hans Jørgen Aagaard Jensen and Hans Ågren started the programming of a second-order, direct MCSCF program SIRIUS. Soon Trygve Helgaker and Poul Jørgensen joined the project. Over the years the author list has expanded with contributions by PhD students and postdocs in the group of the original four authors, and later several of these established their own groups and continued to contribute. As you can see, today the author list has become very, very long -- and it is a great pleasure for the four founding authors to see how useful our initial seeds of code have been for development of many unique electronic structure methodologies.

In 2006 Poul Jørgensen and Trygve Helgaker started an ambitious project with the ultimate research goal of linear scaling DFT. The development started in our common framework, Dalton, but as the linear scaling methodology is intrinsically AO based, while the rest of Dalton is intrinsically MO based (although quite a few tasks can be done in AO basis for efficiency), at the end there was very little overlap in code between the linear scaling code and the Dalton code. The Dalton author community therefore decided at its meeting in January 2010 in Oslo to release the linear scaling code as a separate executable, LSDalton.

Release history


Dalton2018.1 patch is released.


Dalton2018 suite is released.


LSDalton2016.3 patch is released.


LSDalton2016.2 patch is released.


Dalton2016 is released. Note that users with a licence for Dalton2015 or previous versions must re-register to obtain a licence for Dalton2016.

See the program description for a description of all the new (and old) features.


Dalton2015.1 patch is released.


Dalton2015 is released. Note that users with a licence for Dalton2013 or previous versions must re-register to obtain a licence for Dalton2015.

See the program description for a description of all the new (and old) features.


Dalton2013 is released. Note that users with a licence for Dalton2011 or previous versions must reregister to obtain a licence for Dalton2013.


Dalton2011 is released.


Dalton 2.0 is released.

Additions to Dalton 2.0 include DFT implemented up to quadratic response theory, for a wide variety of properties such as molecular Hessians and magnetic-resonance parameters. Also available is the NEVPT2 approach for calculating accurate energetics of multireference systems and the explicitly correlated MP2-R12 method.


Dalton 1.2.1 is released.


Dalton release 1.2 is released. The functionality of the program has been extended significantly! The main new features are coupled-cluster (CC) wave functions and properties, non-equilibrium solvation, the use of Configuration State Functions (CSF) in property calculations, Atomic Mean-Field (AMFI) Approximation, effective core-potentials (ECP), generalized numerical derivatives, temperature-dependant vibrational averaging, Magnetic Circular Dichroism (MCD) and relativistic corrections (Douglas-Kroll).


Dalton 1.1 is released.


Dalton 1.0 is released.

Number of issued licenses

At the release of Dalton 2.0 in March 2005, a total of 1208 licences for Dalton 1.x had been issued.
At the release of Dalton2011 in July 2011, a total of 1898 licences for Dalton 2.0 had been issued.
At the release of Dalton2013 in November 2013, a total of 985 licences for Dalton2011 had been issued: 813 personal, 162 site, and 10 benchmark licences.
At the release of Dalton2015 in February 2015, a total of 692 licences for Dalton2013 had been issued: 579 personal, 104 site, and 9 benchmark licences.