10.1021/acs.jctc.8b01176.s002
Christoph Bannwarth
Christoph
Bannwarth
Sebastian Ehlert
Sebastian
Ehlert
Stefan Grimme
Stefan
Grimme
GFN2-xTBAn Accurate and Broadly Parametrized
Self-Consistent Tight-Binding Quantum Chemical Method with Multipole
Electrostatics and Density-Dependent Dispersion Contributions
American Chemical Society
2019
barrier heights
biomolecular systems
Significant improvements
Multipole Electrostatics
GFN 2-xTB
tight-binding model
order density fluctuation effects
element-specific parameters
D 4 London dispersion model
noncovalent interaction energies
precursor GFN-xTB
1000 atoms
multipole moments
tight-binding picture
Density-Dependent Dispersion Contributions
benchmark sets
GFN 2-xTB method
Parametrized Self-Consistent Tight-Binding Quantum Chemical Method
sound method
order density fluctuations
2019-02-08 23:15:19
Dataset
https://acs.figshare.com/articles/dataset/GFN2-xTB_An_Accurate_and_Broadly_Parametrized_Self-Consistent_Tight-Binding_Quantum_Chemical_Method_with_Multipole_Electrostatics_and_Density-Dependent_Dispersion_Contributions/7698200
An
extended semiempirical tight-binding model is presented, which
is primarily designed for the fast calculation of structures and noncovalent
interaction energies for molecular systems with roughly 1000 atoms.
The essential novelty in this so-called GFN2-xTB method is the inclusion
of anisotropic second order density fluctuation effects via short-range
damped interactions of cumulative atomic multipole moments. Without
noticeable increase in the computational demands, this results in
a less empirical and overall more physically sound method, which does
not require any classical halogen or hydrogen bonding corrections
and which relies solely on global and element-specific parameters
(available up to radon, <i>Z</i> = 86). Moreover, the atomic
partial charge dependent D4 London dispersion model is incorporated
self-consistently, which can be naturally obtained in a tight-binding
picture from second order density fluctuations. Fully analytical and
numerically precise gradients (nuclear forces) are implemented. The
accuracy of the method is benchmarked for a wide variety of systems
and compared with other semiempirical methods. Along with excellent
performance for the “target” properties, we also find
lower errors for “off-target” properties such as barrier
heights and molecular dipole moments. High computational efficiency
along with the improved physics compared to its precursor GFN-xTB
makes this method well-suited to explore the conformational space
of molecular systems. Significant improvements are furthermore observed
for various benchmark sets, which are prototypical for biomolecular
systems in aqueous solution.