PC GAMESS/Firefly TIME DEPENDENT HARTREE-FOCK MODULE $TDHF group required when RUNTYP=TDHF required when CITYP=TDHF For description of $TDHF group for RUNTYP=TDHF frequency-dependent (hyper)polarizabilities calculations please refer to the generic documentation. The only related point which should be mentioned here is that starting from the PC GAMESS v. 7.0 build # 3448, TDHF and DFT code were extended to allow calculation of static and dynamic (hyper)polarizabilities using runtyp=tdhf. For DFT, alpha values are exact, while beta and gamma are only approximate at present, as second-order (and higher) exchange-correlation kernels are not properly taken into account. This will be fixed when TDDFT gradient code will be incorporated into the future PC GAMESS/Firefly versions. The rest of this document is devoted to CITYP=TDHF runs for TDHF (a.k.a. RPA) excitation energies. Current implementation allows the use of only RHF references, but can pick up both singlet and triplet excited states. Nuclear gradients are not yet programmed. Properties are available using "unrelaxed" density. Due to efficiency considerations, TDHF is programmed for SAPS (spin-adapted antisymmetrized product) basis only, so you cannot get both singlet and triplet states at once. NCORE = n Omits the first n occupied alpha and beta orbitals from the calculation. The default for n is the number of chemical core orbitals. NSTATE = Number of states to be found (excluding the ground state). ISTATE = State for which properties and/or gradient will be calculated. Only one state can be chosen. MULT = Multiplicity (1 or 3) of the singly excited SAPS (the reference is necessarily single RHF). DIAGZN = Hamiltonian diagonalization method. = DAVID use Davidson diagonalization. (default) = FULL construct the full matrix in memory and diagonalize, thus determining all states (not recommended except for small cases). NGSVEC = Dimension of the Hamiltonian submatrix that is diagonalized to form the initial CI vectors. The default is the greater of NSTATE*2 and 10. MXVEC = Maximum number of expansion basis vectors in the iterative subspace during Davidson iterations, before the expansion basis is truncated. The default is the larger of 8*NSTATE and NGSVEC. NDAVIT = Maximum number of Davidson iterations. Default=50. DAVCVG = Convergence criterion for Davidson eigenvectors. Eigenvector accuracy is proportional to DAVCVG, while the energy accuracy is proportional to its square. The default is 3.0E-05. RDTDVC = Flag to read TDHF vectors from a $TDVEC group in the input file. Default is .FALSE. MNMEOP = Flag to force the use of the minimal amount of memory during the Davidson iterations. This is for debug purposes. The default is .FALSE. MAXGC - maximum allowed number of trial vectors to be routed through GENCON engine, default is 1. If the number of trial vectors is greater than MAXGC, only FASTINTS will be used. The reason is that for moderately contracted GC basis sets like cc-pVXZ, gencon is faster than fastints only for relatively small number of trial vectors (this is by gencon design). On the other hand, for ANO-like basis sets, it is always better to set MAXGC to be equal the number of initial guess vectors, as fastints will be much slower. PRTTOL - threshold for TDHF csf printout and also for states symmetry determination. Default is 0.05. ISTSYM - symmetry of states of interest. Default is zero, i.e., does not use any symmetry during calculations. Setting this to the desired index of irrep (according to PC GAMESS/Firefly numbering) will solve only for the states of the desired symmetry and exploiting full (including non-abelian) symmetry of molecule, thus significantly reducing computation time. The state-tracking feature of the PC GAMESS/Firefly' TDHF code can be activated by selecting negative value of istate in the $TDHF group. It is intended for geometry optimization of the excited states in the case of root flipping. Note that oscillator strengths printed in the TDHF summary table are calculated using transition dipoles length form only. ========================================================== $TDVEC group required if RDTDVC in $TDHF is chosen This is formatted data generated by a previous TDHF run, to be read back in as starting vectors. ========================================================== Below is the sample input file: $CONTRL SCFTYP=RHF CITYP=TDHF $END $SYSTEM TIMLIM=3000 MEMORY=3000000 $END $BASIS GBASIS=n31 ngauss=6 NDFUNC=1 $END $TDHF NSTATE=3 ISTSYM=0 ISTATE=1 $END $DATA H2O CNV 2 O 8.0 0.0000000000 0.0000000000 0.7205815395 H 1.0 0.0000000000 0.7565140024 0.1397092302 $END

- Fast Matrix Diagonalization and Inversion
- 64-bit processing support
- Spherical Basis Functions
- Fast Two-electron Integral Code
- Additional comments on Two-electron Integral code selection
- Quantum Fast Multipole Method
- Configuration Interaction Singles
- Time-dependent DFT
- CI and Multi-Configuration SCF
- Multi-Configuration Quasi-Degenerate Perturbation Theory
- Extended Multi-Configuration Quasi-Degenerate Perturbation Theory (XMCQDPT)
- PC GAMESS/Firefly' NBO code
- Cube Files
- Multicore, SMP and HTT support
- P2P Parallel Mode Communication Interface, Dynamic Load Balancing, and large-scale MP2 Energy code
- Parallel Linux Instructions: list of supported MPI implementations
- Parallel Windows Instructions: list of supported MPI implementations/bindings

Last updated: March 18, 2009