DFTB Manual 2026.1
******************

The DFTB engine implements Density Functional based Tight-Binding
methods, which can be viewed as computationally efficient
approximations to density functional theory (DFT). As such it is a
good engine for fast calculations that still include quantum effects.
It can be used for molecules and for systems of any periodicity (3D,
2D, or 1D).

**Table of Contents:**


Table of contents
^^^^^^^^^^^^^^^^^

* General

  * Introduction

  * What's new in DFTB?

    * New in DFTB2025.1

    * New in DFTB2024.1

    * New in DFTB2023.1

    * New in DFTB2022.1

    * New in DFTB2021.1

    * New in DFTB2020

    * New in DFTB2019.3

    * New in DFTB2019.1

    * New in DFTB2018

* AMS driver's tasks and properties

  * Geometry, System definition

  * Tasks: exploring the PES

  * Properties in the AMS driver

* Model Hamiltonians

  * Slater-Koster based DFTB

  * Extended tight-binding (xTB)

  * Model Hamiltonian

  * Dispersion correction

  * Solvation (GBSA)

  * QM/FQ Embedding

  * SCC details and spin-polarization

    * MultiStepper

    * DIIS

  * k-space integration

  * xTB specific keywords

  * Technical options

* Spectroscopy and properties

  * Electronic structure of periodic systems

  * Excited states with time-dependent DFTB

  * Excited state gradients

  * Frequencies, phonons, VCD

  * Vibrationally resolved electronic spectra

  * Stress tensor, Elasticity

  * Charges, Bond Orders, Dipole Moment, Polarizability

  * Fragment orbital analysis

  * NBO analysis

* Electronic transport (NEGF)

  * Transport with NEGF in a nutshell

  * Simulation workflow

  * Conductance input options

  * Miscellaneous remarks on DFTB-NEGF

* Charge transport (transfer integrals)

  * Charge transfer integrals direct method

* Parameterizations

  * Parameter meta-info

  * Slater-Koster based DFTB

    * Available parameter sets

    * Files in the resources directory

  * Extended tight-binding (xTB)

* Required citations

  * General references

  * Parameter references

* References

  * Slater-Koster based DFTB

    * General Description

    * Parameter sets

    * QUASINANO2015

    * Dresden

    * DFTB.org

  * Extended tight-binding (xTB)

  * External programs and Libraries

* Examples

* Keywords

* KF output files

* FAQ
