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cceom(1) [debian man page]

optking(1)																optking(1)

       cceom - equation of motion coupled cluster energy program

       DESCRIPTION

       The program cceom calculates EOM-CCSD energies using a Davidson algorithm to solve for the right-hand eigenvectors of the CC Hamiltonian.

       COMMAND LINE ARGUMENTS

       After internal coordinates are detected or generated, optking will enter a run-time mode dependent on command line arguments.

       --dot_with_Lg	-  check the orthogonality of the excited right-hand eigenvector with
			-  the ground state left eigenvector, lambda.  cclambda must be run
			- first for this to work

       REFERENCES

       1.     The  equation  of  motion  coupled-cluster  method.  A systematic biorthogonal approach to molecular excitation energies, transition
	      probabilities, and excited state properties, J. F. Stanton and R. J. Bartlett, J. Chem. Phys. 98, 7029 (1993).

       EOM_REFERENCE = integer
	      specifies the algorithm used by cceom.  useful for debugging.  also must currently be set to  ROHF,  if  you  want  to  get  triplet
	      excited states from a singlet ground state.  The default is whatever "REFERENCE" is.

       STATES_PER_IRREP = array of integers
	      specifies  the  number  of states of each irreducible representation desired.  For example, in C2v symmetry, (0 2 0 0) specifies two
	      excited states of A2 symmetry to be solved, regardless of the symmetry of the ground state.

       PROP_SYM = integer
	      specifies the symmetry of the state that should be used to compute properties.  defaults to the last  irrep  for	which  states  are
	      requested.

       PROP_ROOT = integer
	      specifies  the  number  of  the  root  (within  its  irrep) that should be used to compute properties.  defaults to the highest root
	      requested.

       EXCITATION_RANGE = excitation_range
	      used to generate initial guesses.  the larger the value, the more initial guesses are made in the Davidson algorithm.

       RESIDUAL_TOL = integer
	      Davidson algorithm will converge until the norm of the residual vector is less than 10^(-integer).  default if 4.

       EVAL_TOL = integer
	      Davidson algorithm will converge until the change in the excitation energy is less than 10^(-integer).  default if 6.

								     Sept 2002								optking(1)

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mp2(1)																	    mp2(1)

NAME
mp2 - Moller-Plesset Perburbation Theory DESCRIPTION
The module determines the second-order Moller-Plesset energy and one-particle density matrix (OPDM) for RHF, UHF, and ROHF (using semi- canonical orbitals) references. Frozen orbitals can be used when computing the energy but not the OPDM. REFERENCES
Original Moller-Plesset paper: 1. C. Moller and M. S. Plesset, "Note on an Approximation Treatment for Many-Electron Systems," Phys. Rev. 46, 618 (1934). Open-Shell Perturbation Theory 1. T. D. Crawford, H. F. Schaefer, and T. J. Lee, "On the energy invariance of open-shell perturbation theory with respect to unitary transformations of molecular orbitals," J. Chem. Phys. 105, 1060 (1996). MP(2) Gradient Theory: 1. M. Frisch, M. Head-Gordon, and J. Pople, "A Direct MP2 Gradient Method," Chem. Phys. Lett. 166, 275 (1990). 2. I. Nielsen, "A new direct MP2 gradient algorithm with implementation on a massively parallel computer," Chem. Phys. Lett. 255, 210 (1996). INPUT FORMAT
Input for this program is read from the file input.dat. The following keywords are valid: WFN = string Specifies the type of wave function desired. The only valid entry at the present is MP2. There is no default. REFERENCE = string Specifies the type of orbitals used for the single-determinant reference function. Valid entries include RHF, UHF, and ROHF. There is no default. PRINT = integer Determines the verbosity of the output. A value of 0 (the default) specifies minimal printing. CACHETYPE= string Selects the priority type for maintaining the automatic memory cache used by the DPD codes. (See libdpd.html for further details.) A value of LOW (the default) selects a "low priority" scheme in which the deletion of items from the cache is based on pre-pro- grammed priorities. A value of LRU selects a "least recently used" scheme in which the oldest item in the cache will be the first one deleted. CACHELEV= integer Selects the level of automatic cacheing desired in the storage of various amplitudes, integrals, and intermediates in the coupled cluster procedure. A value of 0 retains no quantities in cache, while a level of 6 attempts to store all quantities in cache. For particularly large calculations, a value of 0 may help with certain types of memory problems. The default is 2, which means that all four-index quantites with up to two virtual-orbital indices (e.g., <ij|ab> integrals) may be held in the cache. OPDM = boolean If TRUE calculate the one-particle density matrix and make OPDM_WRITE default to TRUE. The default value of OPDM is FALSE. OPDM_WRITE = boolean Flag for whether or not to write the one-particle density matrix to disk. OPDM_PRINT = boolean Flag for whether or not to print the one-particle density matrix. 10 August, 2003 mp2(1)
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