FULLY << EOF ... program data ... EOFThe program can perform FULL-CI calculations on systems with at most 255 orbitals.
The program recognizes the ATMOL predirectives as described in the introduction manual. The program uses the UNIX memory allocation mechanism to arrange its core memory. The default core size is 0 words, therefore the predirectives are needed to specify the amount of core memory for the program.
The first set of program directives contains directives that should be supplied before the directives of the second set.
The MFILE Directive
This directive is used to define the location of the MAINFILE. The syntax has been given in the description of the ATMOL SCF program .
Example 1: MFILE ED2 75 0Omission of the MFILE directive is equivalent to:
MFILE ED2 1 0
The TITLE Directive
Allows the user to define an 80 character title for the run, and extends over two lines. The first line consists of the character string TITLE in the first data field, the second line the user defined title.
Example: TITLE PROPANE FULL-CI
The FULLCI Directive
The fullci directive allows the user to specify the number of orbitals, the number of electrons and the spin state. The directive has the syntax:
FULLCI NORB NAPHA NBETAwhere
2 =< NORB =< 255Furthermore, note that
NALPHA >= NBETAshould hold.
The ONELEC Directive
The ONELEC directive allows the user to specify the location of the DUMPFILE and the transformed 1-electron integrals placed thereon by the integral transformation program. The syntax is
ONELEC DDNAM IBLK ISECT
DDNAM = "ED3" IBLK = 1 ISECT = 198will be taken.
The CRIT Directive
This directive provides a automatic way of specifying the symmetry data. The syntax is
ICRIT = 7
The FINISH Directive
This should be the last directive presented. The program collates all the previous data and checks it for obvious errors, and commences the CI calculation. The syntax is
The second set of program directives contains directives that should be supplied after the directives from the first set.
The ROOTS Directive
This directive defines the number of roots that should be calculated. The directive has the syntax:
The MAXCYC Directive
This directive allows the specification of the maximum number of iterations. The directive has the syntax:
1 =< MAXIT =< 50The default maximum number of iterations is 50.
The THRESH Directive
This directive allows the specification of the convergence threshold. The directive has syntax:
THRESH IFACTOR IEXPwhere
ACCURACY = DBLE(IFACTOR) * (10.0D0 ** IEXP)By default the accuracy is 5.0D-4.
The SYMMETRY Directive
This directive allows the specification of the irreducible representation of the required states. The directive has syntax:
1 =< ISYMM =< 8The default value of ISYMM is 1.
The PRINT Directive
This directive specifies the minimal size for Ci-vector coefficients to be printed. Coefficients smaller than the specified size will not be printed. The directive has syntax:
PRINT IFACTOR IEXPwhere
PRINTING_THRESHOLD = DBLE(IFACTOR) * (10.0D0 ** IEXP)By default the accuracy is 5.0D-2.
The GUESS Directive
This directive allows the specification of the number of guess Ci-vectors that will be supplied for the diagonalisation routine. The directive has syntax:
The SINGLE Directive
This directive offers the specification of the symmetry of the desired states by multiplying the symmetry of a set of orbitals. The directive has syntax:
SINGLE [ IORB1 [ IORB2 [ ... ] ] ] 0where
Example 1: SINGLE 1 2 3 4 5 0
Example 2: SINGLE 1 2 3 0 SINGLE 4 5 0
The ENTER Directive
This directive terminates the directive driven input and starts the calculation.
Listed are error strings that may occur and a corresponding explaination.