Mopac_Hamiltonian contains the procedure which is used to define the quantum mechanical atoms in the system.
Module | Variables |
---|---|
CONSTANTS | AMU_TO_KG, EV_TO_KJ, KBOLTZ, KCAL_TO_KJ, NAVOGADRO, PI, PLANCK |
DEFINITIONS | DP |
ELEMENTS | NELEMENTS |
STATUS | ERROR |
ATOMS | ATMMAS, ATMNAM, ATMNUM, ATMQMI, NATOMS, NATOMSMM, NATOMSQM |
GAUSSIAN_BASIS | Most public items in the module. |
MM_TERMS | ANGLES, ATMCHG, ATMCHG14, ATMEPS, ATMEPS14, ATME14I, ATME14J, BONDS, DIHEDRALS, IMPROPERS, NANGLES, NBONDS, NDIHEDRALS, NIMPROPERS |
MOPAC_DATA | Most public items in the module. |
MOPAC_DENSITY | DENSITY_GUESS |
MOPAC_PARAMETER | Most public items in the module. |
None.
There is a single public subroutine in this module.
Subroutine | Purpose |
---|---|
MOPAC_SETUP | Define the quantum mechanical atoms in the system. |
Argument | Type | Intent | Optional | Purpose |
---|---|---|---|---|
METHOD | Character ( Len = * ) | In | No | The semi-empirical method to use. |
CHARGE | Integer | In | Yes | The total charge on the quantum mechanical atoms. |
MULTIPLICITY | Integer | In | Yes | The system's multiplicity. |
SELECTION | Logical(1:NATOMS) | In | Yes | An atom selection array. |
LINK_ATOM_DISTANCES | Real(:) | In | Yes | The link-atom distances. |
PIATOMS | Integer | In | Yes | The path-integral atom definitions. |
PITEMPERATURE | Real | In | Yes | The temperature for a path-integral simulation. |
Error | Meaning |
---|---|
Unknown MOPAC Hamiltonian. | The METHOD argument is not one of the strings "AM1", "MNDO" or "PM3". |
Invalid MULTIPLICITY. | The system does not have a multiplicity of 1. |
A PI atom is not quantum. | All path-integral atoms must be quantum mechanical atoms too. |
Data mismatch between equivalent PI atoms in different polymers. | There is a mismatch in the masses or the atomic numbers of equivalent atoms in different path-integral polymers. |
An atom occurs more than once in the definition of the PI atoms. | An atom can only occur once in the definition of the path-integral atoms. |
An atom has an invalid atomic number. | An atom has an atomic number of less than 1 or more than NELEMENTS. |
Parameters unavailable for an element. | The semi-empirical method requested has not been parametrized for an element. |
Only S and SP elements allowed. | D functions are not yet implemented in the program. |
There are an odd number of electrons. | The multiplicity of the system is not 1. |
LINK_ATOM_DISTANCES argument has the wrong size. | The number of link atoms to be added to the system is not the same as the size of the LINK_ATOM_DISTANCES array. |
LINK_ATOM_DISTANCES argument present but there are no boundary atoms. | No link atoms need to be placed in the system and yet the LINK_ATOM_DISTANCES array was specified. |
Stable.