9.1 Functionalities of MPGRAD, and RICC2, and PNOCCSD
Functionalities of mpgrad:
- Calculation of MP2 energies and/or MP2 gradients for RHF and UHF wave functions.
- The frozen core approximation (possibility to exclude low-lying orbitals from the MP2
treatment) is implemented only for MP2 energies.
- Exploitation of symmetry of all point groups.
- Can be used sequentially or MPI-parallel.
- Can be combined with the COSMO solvation model (see chapter 17.2 for details).
(Presently restricted to sequential calculations.)
Functionalities of ricc2 at the MP2 level:
- Calculation of MP2 energies and/or gradients for RHF and UHF wave functions
within the RI approximation (RI-MP2). In geometry optimizations and vibrational
frequency calculations (with NumForce) it can be combined with RI-JK-SCF for the
Hartree-Fock reference calculation.
- The frozen core approximation is implemented for both energies and gradients.
- RI-MP2 needs optimised auxiliary basis sets, which are available for most standard
basis sets as e.g. SVP, TZVP, TZVPP, QZVPP as well as for the (aug-)cc-p(wC)VXZ
(X = D, T, Q, 5) basis set series (for Al–Ar also for the (aug-)cc-p(wC)V(X+d)Z
series and for p-block elements Ga–Rn also the respective ECP basis set series (-pp)).
- Exploitation of symmetry for all point groups for MP2 energies and gradients.
- Can be combined with the COSMO solvation model (see chapter 17.2 for details).
- Runs sequentially and parallel (with MPI, OpenMP and hybrid MPI/OpenMP)
- Contains an implementation of explicitly correlated MP2-F12 methods (presently
restricted to energies and the C1 point group).
- Can for open-shell calculations be used with UHF and single-determinant high-spin
ROHF reference wavefunctions. (ROHF-MP2 presently limited to energies.)
- Energies and gradients for the spin-component scaled SCS- and SOS-MP2 approaches,
including a Laplace-transformed implementation of SOS-MP2 with (4) scaling
computational costs.
- Static polarizabilities (currently restricted to closed-shell reference wavefunctions and
the sequential and SMP versions; cannot yet be combined with spin-component
scaling), see Chapter 10.5 for a description of the input
- See Chapter 10 for further details.
Functionalities of pnoccsd:
- Currently restricted to MP2 and DFT double hybrid (e.g. B2PLYP) single point
energy calculations with a closed shell reference determinant and the C1 point group.
- Runs sequentially and parallel (with MPI, OpenMP and hybrid MPI/OpenMP).
- Contains an implementation of explicitly correlated PNO-MP2-F12 methods.
- See Section 9.7 for further details.
9.1.1 How to quote
- For calculations with mpgrad:
Semi-direct MP2 Gradient Evaluation on Workstation Computers: The MPGRAD
Program. F. Haase and R. Ahlrichs; J. Comp. Chem. 14, 907 (1993).
- For calculations with ricc2:
CC2 excitation energy calculations on large molecules using the resolution of the
identity approximation. C. Hättig and F. Weigend;
- for MPI parallel calculations with ricc2 in addition:
Distributed memory parallel implementation of
energies and gradients for second-order Møller-Plesset perturbation theory with the
resolution-of-the-identity approximation. Christof Hättig, Arnim Hellweg, Andreas
Köhn, Phys. Chem. Chem. Phys. 8, 1159-1169, (2006).
- for MP2-F12 calculations in addition:
The MP2-F12 Method in the TURBOMOLE Programm Package. Rafal A. Bachorz,
Florian A. Bischoff, Andreas Glöß, Christof Hättig, Sebastian Höfener, Wim Klopper,
David P. Tew, J. Comput. Chem. 32, 2492–2513 (2011).
- for (4)-scaling LT-SOS-MP2 calculations:
Scaled opposite-spin CC2 for ground and excited states with fourth order scaling
computational costs. Nina O. C. Winter, Christof Hättig, J. Chem. Phys., 134, 184101
(2011) and Scaled opposite-spin second order Møller–Plesset correlation energy: An
economical electronic structure method. Y., Jung, R.C. Lochan, A.D. Dutoi, and
M. Head-Gordon, J. Chem. Phys., 121, 9793 (2004).
- for SCS-MP2 calculations:
S. Grimme, J. Chem. Phys. 118, 9095 (2003).
- for RI-MP2 polarizabilities:
Large scale polarizability calculations using the approximate coupled cluster model
CC2 and MP2 combined with the resolution-of-the identity approximation. Daniel H.
Friese, Nina O. C. Winter, Patrick Balzerowski, Raffael Schwan, Christof Hättig, J.
Chem. Phys., 136, 174106 (2012).
- for PNO-MP2 calculations: A (3)-scaling PNO-MP2 method using a hybrid
OSV-PNO approach with an iterative direct generation of OSVs. Gunnar Schmitz,
Benjamin Helmich, Christof Hättig, Mol. Phys. 111, 2463–2476, (2013).
- for explicitly correlated PNO-MP2-F12 calculations: Explicitly correlated PNO-MP2
and PNO-CCSD and its application to the S66 set and large molecular systems.
Gunnar Schmitz, Christof Hättig, David Tew, Phys. Chem. Chem. Phys. 16,
22167–22178 (2014).