TURBOMOLE manual
v8.0

1.6 Modules and Their Functionality

For references see Bibliography.

define

interactive input generator which creates the input file control.
define supports all basis sets available from the basis set library, especially the fully atom optimized consistent basis sets of SVP, TZV and QZV quality [6, 7, 8, 9, 10] available for the atoms H–Rn. define determines the molecular symmetry and internal coordinates which allow efficient geometry optimization. define allows to perform a geometry optimization at a force field level to preoptimize the geometry and to calculate a Cartesian Hessian matrix. define sets the keywords necessary for single point calculations and geometry optimizations within a variety of methods. There are also many features to manipulate geometries of molecules: just try and see how it works.

uff 

performs a geometry optimization at a force field level. The Universal Force Field (UFF) [11] is implemented. Beyond this it calculates an analytical Hessian (Cartesian) which can be used as a start Hessian for an ab initio geometry optimization.

dscf 

for (semi–)direct SCF–HF and DFT calculations (see keywords for functionals supported). dscf supports restricted closed-shell (RHF), spin-restricted ROHF as well as UHF runs. dscf includes an in-core version for small molecules.

grad 

requires a successful dscf run and calculates the gradient of the energy with respect to nuclear coordinates for all cases treated by dscf.

perform (direct) SCF–HF and DFT calculations—as dscf and grad—within the very efficient (multipole accelerated) RI–\(J\) approximation for the interelectronic Coulomb term. These programs also permit to approximate HF exchange within the RI–\(K\) approximation or using semi-numerical techniques. The exchange correlation functionals supported are specified in define. Relativistic two-component calculations are also available.

riper 

performs DFT calculations for molecules and periodic systems using the RI technique. In addition, a low-memory RI implementation based on preconditioned conjugate gradient algorithm is available for molecular systems. Furthermore, a real time-time dependent DFT implementation based on Magnus expansion for the time evolution operator is available for molecular systems. Both RHF and UHF runs are supported. Currently hybrid functionals are not supported.

mpgrad

requires a well converged SCF run—by dscf, see keywords—and performs closed-shell RHF or UHF calculations yielding single point MP2 energies and, if desired, the corresponding gradient. Note that mpgrad performs conventional, i.e. non-RI MP2 calculations only. For real-life applications it is highly recommended to use RI-MP2 instead (see module ricc2).

ricc2

calculates electronic ground and excitation energies, transition moments and properties of ground and excited states at the MP2, CIS, CIS(D), ADC(2) and CC2 level using either a closed-shell RHF or a UHF SCF reference function. Calculates R12 basis set limit correction for MP2 energies. Employs the RI technique to approximate two-electron integrals.

[12, 13, 14, 15, 16, 17, 18, 19].

ccsdf12

calculations of electronic ground state energies beyond MP2/CC2:
RI-MP2-F12, MP3, MP3-F12, MP4, MP4(F12*), CCSD, CCSD(F12), CCSD(F12*), CCSD(F12)(T), CCSD(F12*)(T) and electronic excitation energies at the CCSD level.[20, 21, 22, 23]

pnoccsd

calculations of electronic ground state energies with PNO-based methods starting from MP2 and MP2-F12 up to PNO-CCSD(T).[24, 25]

relax

requires a gradient run—by grad, rdgrad, ricc2, egrad, or mpgrad—and proposes a new structure based on the gradient and the approximated force constants. The approximated force constants will be updated. This module will not be used by default any more if jobex is called.

statpt

performs structure optimization using the "Trust Radius Image Minimization" algorithm. It can be used to find minima or transition structures (first order saddle points). Transition structure searches usually require initial Hessian matrix calculated analytically or the transition vector from the lowest eigenvalue search.

frog

executes one molecular dynamics (MD) step. Like relax, it follows a gradient run: these gradients are used as classical Newtonian forces to alter the velocities and coordinates of the nuclei.

aoforce

requires a well converged SCF or DFT run—by dscf or ridft, see keywords—and performs an analytic calculation of force constants, vibrational frequencies and IR intensities. aoforce is also able to calculate only the lowest Hessian eigenvalues with the corresponding eigenvectors which reduces computational cost. The numerical calculation of force constants is also possible (see tool NumForce in Section 1.7).

escf

requires a well converged SCF or DFT run and calculates time dependent and dielectric properties (spin-restricted closed-shell or spin-unrestricted open-shell reference):

  • static and frequency-dependent polarizabilities within the SCF approximation

  • static and frequency-dependent polarizabilities within the time-dependent Kohn–Sham formalism, including hybrid functionals such as B3-LYP

  • electronic excitations within the RHF and UHF CI(S) restricted CI method

  • electronic excitations within the so-called SCF-RPA approximation (poles of the frequency dependent polarizability)

  • electronic excitations within the time dependent Kohn–Sham formalism (adiabatic approximation). It can be very efficient to use the RI approximation here, provided that the functional is of non-hybrid type: we recommend B-P86 (but slightly better results are obtained for the hybrid functional B3-LYP) [26].

  • stability analysis of single-determinant closed-shell wave functions (second de­rivative of energy with respect to orbital rotations) [27].

  • relativistic two-component calculations [28, 29, 30]

  • Bethe–Salpeter equation (BSE) [31, 32, 30, 33, 34] and the GW method [35, 36, 37, 38]

egrad

computes gradients and first-order properties of excited states. Well converged orbitals are required. The following methods are available for spin-restricted closed shell or spin-unrestricted open-shell reference states:

  • CI-Singles approximation (TDA)

  • Time-dependent Hartree–Fock method (RPA)

  • Time-dependent density functional methods

egrad can be employed in geometry optimization of excited states (using jobex, see Section 5.1), and in finite difference force constant calculations (using NumForce). Details see [39].

rirpa

calculates ground state energies and analytic first-order properties within the random phase approximation (RPA) and its perturbative corrections, see Section 13. A Kramers-restricted two-component formalism is implemented for ground state energies.

mpshift

computes NMR chemical shieldings for all atoms of the molecule at the SCF, DFT or MP2 level within the GIAO or CGO ansatz and the (CPHF) SCF approximation. From this one gets the NMR chemical shifts by comparison with the shieldings for the standard compound usually employed for this purpose, e.g. TMS for carbon shifts. In molecules with ECP-carrying atoms, chemical shieldings on all the other atoms can be computed with mpshift [40, 41] in the way suggested in J. Chem. Phys. 136, 114110 (2012). Alternatively, scalar-relativistic and spin–orbit all-electron X2C is available to treat heavy elements [42, 43, 44]. The (multipole accelerated) RI–\(J\) approximation is supported [45]. mpshift and aoforce can be used to calculate vibrational circular dichroism (VCD) spectra [46]. mpshift can also be employed to calculate EPR properties. DFT calculations should not be performed with gridsize m3 or m4.

freeh

calculates thermodynamic functions from molecular data in a control file; an aoforce or a NumForce run is a necessary prerequisite.

evib

calculates the matrix elements of the first order derivative of the Kohn–Sham operator with respect to atomic displacements and describes the first order electron-vibration (EV) interaction.

intense

calculates Raman scattering cross sections from molecular data in a control file; an aoforce and an egrad run are a necessary prerequisite. Please use the Raman script to run these three steps in an automated way.

woelfling

computes a finite number of structures along reaction paths within different interpolation algorithms. It provides an initial path using a modified Linear Synchronous Transit. See Section 5.9 for details. Please use the woelfling-job script to run optimizations with it.

proper

computes a variety of first-order properties and provides several functionalities to analyse wavefunctions such as orbital localization, population analysis, natural transition orbitals, AIM critical points and paths, etc. and can generate output in a variety of plotting formats (see chapter 22).