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⟦5f219cb25⟧ TextFile

    Length: 16128 (0x3f00)
    Types: TextFile
    Names: »mchfex«

Derivation

└─⟦00964e8f7⟧ Bits:30007478 RC8000 Dump tape fra HCØ.
    └─⟦b2ec5d50f⟧ 
        └─⟦this⟧ »mchfex« 

TextFile

C     ------------------------------------------------------------------
C     2-1     E X A M P L E   1
C     ------------------------------------------------------------------
C
C     THE FIRST EXAMPLE ILLUSTRATES HOW DATA CAN BE SET UP FOR AN
C     ISOELECTRONIC SEQUENCE.  NOTE THAT FOR EACH ATOM OR ION, THE
C     SLATER INTEGRALS AND RADIAL FUNCTIONS ARE PRINTED.  THE LATTER
C     ALSO ARE OUTPUT, A FUNCTION AT A TIME, FOR FUTURE INPUT.
C
  5  5  0  0
  6  6  7  0
 BE    1S      4.    180  2  2  1
  1S2/2S2
 1S  1  0  0.0   1  0  0  2
 2S  2  0  3.0   1  0  0  2
  T 12  4
  1  B+    5.0
  T 12  4
  1 C+2    6.0
  T 12  4
  1 O+4    8.0
  T 12  4
  1 NA+7  11.0
  T 12  4
  1 P+11  15.0
  T 12  4
  1 CA+16 20.0
  T 12  4
  1 MN+21 25.0
  T 12  4
  1 ZN+26 30.0
  T 12  4
*
C
C     THOUGH RESULTS ARE MEANINGFUL PHYSICALLY ONLY FOR INTEGRAL
C     VALUES OF Z, A USEFUL FEATURE WHEN DOING CALCULATIONS FOR
C     NEGATIVE IONS WHERE INITIAL ESTIMATES ARE NOT WELL KNOWN, IS
C     THE ABILITY TO TURN OFF THE NUCLEAR CHARGE IN FRACTIONAL STEPS,
C     THEREBY APPROACHING THE RELATIVELY UNSTABLE STATE WITH GOOD
C     INITIAL ESTIMATES.
C
C     ------------------------------------------------------------------
C     2-2    E X A M P L E    2
C     ------------------------------------------------------------------
C
C     THE SECOND EXAMPLE ILLUSTRATES A FIXED CORE CALCULATION.  IN THE
C     FIRST CASE, HARTREE-FOCK CALCULATIONS ARE PERFORMED FOR THE NA+
C     CORE.  THEN, WITH THESE FUNCTIONS FIXED AND STILL IN MEMORY, A
C     FIXED CORE CALCULATION IS PERFORMED FIRST FOR 3S AND THEN FOR 3P.
C     IN THIS CASE NO CALCULATIONS ARE SUMMARIZED  NOR ARE ANY RESULTS
C     PUNCHED. NOTE ALSO THE ZERO OCCUPATION NUMBER FOR 3S IN THE
C     CALCULATION FOR 3P.  THIS IS ALLOWED AS LONG AS THE ASSOCIATED
C     RADIAL FUNCTION IS NOT INCLUDED IN THE SET OF FUNCTIONS BEING
C     MADE SELF-CONSISTENT.
C
  5  5  0  0
  0  0  0  0
 NA+   1S     11.    190  3  3  1
  2S2/2P6
 1S  1  0  0.0   1  0  0  2
 2S  2  0  2.0   1  0  0  2
 2P  2  1  7.0   1  0  0  6
  F 10 10
*
 NA    2S     11.    190  4  1  1
  2S2/2P6/3S
 1S  1  0  0.0   1  0  1  2
 2S  2  0  2.0   1  0  1  2
 2P  2  1  7.0   1  0  1  6
 3S  3  0 10.0   1  0  0  1
  F 10 2
*
 NA    2P     11.    190  5  1  1
  2S2/2P6/3P
 1S  1  0  0.0   1  0  1  2
 2S  2  0  2.0   1  0  1  2
 2P  2  1  7.0   1  0  1  6
 3S  3  0 10.0   1  0  1  0
 3P  3  1 10.0   1  0  0  1
  F 10 2
*
C
C     ------------------------------------------------------------------
C     2-3    E X A M P L E    3
C     ------------------------------------------------------------------
C
C     THIS EXAMPLE ILLUSTRATES THE USE OF MULTIPLE ORBITALS OF THE SAME
C     TYPE.   THIS FEATURE IS RESTRICTED TO CASES WHERE THE INTERACTION
C     BETWEEN CONFIGURATIONS RESULTS IN TERMS WITH AT MOST ONE OVERLAP
C     INTEGRAL.   THESE ARE ALLOWED ONLY FOR RK AND L INTEGRALS AND SO
C     OCCASSIONALLY FK OR GK INTEGRALS MUST BE RE-EXPRESSED AS RK
C     INTEGRALS.
C
C
  5  5  0  0
  0  0  0  0
 B     2P      5.    180  4  4  2  1  0  1
  2S2/2P                 1.0
  2P*3                    0.3
 1S  1  0  0.0   1  0  0  2  2
 2S  2  0  2.0   1  0  0  2
 2P  2  1  4.0   1  0  0  1
2P*  2  1  3.0   3  0  0  0  3
 0.240000000F2( 4 2, 4 2)
 -0.94280904R1( 2 2 1, 4 4 2)< 3! 4> 1
  F  8  1  0  0 .1D-7 .1D-5
*
C
C
C     IN THE ABOVE EXAMPLE THE CFGTOL AND SCFTOL PARAMETERS HAVE BEEN
C     RESET TO LARGER  VALUES THAN THE DEFAULT VALUES AND NO FUNCTIONS
C     ARE PUNCHED.   THIS APPROACH IS USEFUL WHEN A TRIAL CALCULATION
C     IS BEING PERFORMED.
C
C     IN MORE COMPLEX CASES, MORE RESTRICTIONS ARE PRESENT.  NORMALLY
C     AN OFF-DIAGONAL ENERGY PARAMETER CAN BE COMPUTED DIRECTLY FROM
C     A PAIR OF RADIAL EQUATIONS (SEE SEC. 7-3), BUT WHEN NON-ORTHOG-
C     ONAL ORBITALS ARE PRESENT, INDICATED BY THE FACT THAT THEIR NL
C     VALUES ARE THE SAME, IT MAY BE NECESSARY TO SOLVE A SYSTEM OF
C     EQUATIONS FOR SETS OF PARAMETERS.  WHEN ORTHO = .FALSE., THE
C     PROGRAM ASSUMES OFF-DIAGONAL PARAMETERS CAN BE COMPUTED FROM A
C     SINGLE PAIR OF EQUATIONS.  WHEN ORTHO = .TRUE., THE PROGRAM
C     CHECKS IF OTHER ORBITALS ARE PRESENT, NON-ORTHOGONAL TO EITHER
C     ONE OF THE PAIR.  AT MOST ONE SUCH ORBITAL FOR EACH MEMBER CAN
C     BE ACCOMMODATED.  THE IMPLICATION OF THESE RESTRICTIONS CAN BE
C     DESCRIBED FOR THE MCHF CALCULATION --
C             2P6.(3S.3P  +  3P'.3D )
C     IF 2P IS DETERMINED VARIATIONALLY IT MUST BE ORTHOGONAL TO BOTH
C     3P AND 3P' WHICH ARE NON-ORTHOGONAL.  HENCE A SYSTEM OF EQUATIONS
C     MUST BE SOLVED AND WE NEED ORTHO = .TRUE.  ON THE OTHER HAND, IF
C     2P WERE PART OF THE FIXED CORE, THE VALUE OF ORTHO WOULD NOT BE
C     IMPORTANT.  THE CALCULATION FOR
C             2P6.(3S.3P + 4S.4P  + 3P'.3D + 4P'.4D )
C     CAN ONLY BE PERFORMED CORRECTLY WITH 2P PART OF A FIXED CORE.
C     ORTHO MUST BE .FALSE. OTHERWISE ALL FUNCTIONS WITH DIFFERENT NL
C     VALUES WOULD BE MADE ORTHOGONAL.  THE -1 OPTION MUST BE USED TO
C     INCLUDE 4S,4P IN CONFIGURATION 1, 4P',4D IN CONFIGURATION 3
C     FOR ORTHOGONALITY PURPOSES.
C
C
C     ------------------------------------------------------------------
C     2-4    E X A M P L E    4
C    -------------------------------------------------------------------
C
C     THE EXAMPLE BELOW IS A TWO CONFIGURATION PROBLEM WHERE THE INTER-
C     ACTION IS SMALL AND ALL FUNCTIONS MUST BE ORTHOGONAL.  IN SUCH A
C     CALCULATION IT IS IMPORTANT THAT THE FUNCTIONS DEFINING THE DOM-
C     INANT CONFIGURATION BE FAIRLY ACCURATE AND SO A ONE CONFIGURATION
C     CALCULATION IS USED FOR DETERMINING THE INITIAL ESTIMATES.
C
C     THE INTERACTION IN THIS CASE IS SMALL RESULTING IN A SHALLOW
C     ENERGY MINIMUM.  THIS COMBINED WITH THE MANY ORTHOGONALITY CON-
C     STRAINTS MAKES CONVERGENCE DIFFICULT.  THE PROGRAM PRINTS OUT
C     SEVERAL DIRE MESSAGES BUT THESE DISAPPEAR AS CONVERGENCE SETS IN.
C
  5  5  0  0
  0  0  0  0
 HE    3S      2.    180  2  2  1  0  1  0
  1S/2S
 1S  1  0  0.0   1  0  0  1
 2S  2  0  1.0   1  0  0  1
 -.500000000G0( 1 1, 2 1)
  F 12 -1
*
 HE    3S      2.    180  4  2  2  0  2  2  0  T  T
  1S/2S                  0.9965624
 3S/4S                   -.0016
 1S  1  0  0.0   1  0  1  1
 2S  2  0  1.0   1  0  1  1
 3S  3  0 -5.0   3  0  0  0  1
 4S  4  0 -8.7   3  0  0  0  1
 -.500000000G0( 1 1, 2 1)
 -.5        G0( 3 2, 4 2)
 2.0        R0( 1 2 1, 3 4 2)
-2.0        R0( 1 2 1, 4 3 2)
  F 15  1  0  0 .1D-7 .1D-6
*
C
C     NOTE THAT WHEN NO OVERLAP INTEGRALS ARE PRESENT, THEY CAN SIMPLY
C     BE OMITTED.  ALSO, NEGATIVE SCREENING PARAMETERS MAY BE USED TO
C     TO CONTRACT THE VIRTUAL ORBITALS.
C
C
C     ------------------------------------------------------------------
C     2-5    E X A M P L E    5
C     -----------------------------------------------------------------
C
C     ONE OF THE MORE DIFFICULT CASES, HISTORICALLY WAS 1S2S 1S OF HE.
C     THIS IS AN EXAMPLE WHERE LARGE OFF-DIAGONAL ENERGY PARAMETERS
C     OCCUR BECAUSE OF THE ORTHOGONALITY CONSTRAINT, THE EFFECT OF
C     WHICH IS TO ROTATE THE USUAL 1S, 2S ORBITAL BASIS.   ON THE
C     OTHER HAND, THE 1S2S 3S CALCULATION IS A PARTICULARLY SIMPLE
C     ONE.   THE DATA BELOW DESCRIBES A CALCULATION IN WHICH THE
C     OUTPUT FOR 3S DEFINES THE INITIAL ESTIMATES FOR THE 1S STATE.
C
C     IN THIS CASE, THE 1S STATE IS NOT THE LOWEST STATE OF A GIVEN
C     SYMMETRY AND THE HARTREE-FOCK APPROXIMATION IS NOT A PARTICULARLY
C     GOOD ONE, THE TOTAL ENERGY BEING CONSIDERABLY BELOW THE OBSERVED.
C     AN MCHF APPROXIMATION WHICH INCLUDES  1S2 1S  YIELDS A
C     MUCH BETTER RESULT.  SUCH A CALCULATION FOLLOWS THE SINGLE
C     CONFIGURATION CASE BELOW, WITH 3S FUNCTIONS AGAIN SERVING
C     AS INITIAL ESTIMATES.
C
C
  5  5  0  0
  0  0  0  0
 HE    3S      2.    180  2  2  1  0  1  0
  1S/2S
 1S  1  0  0.0   1  0  0  1
 2S  2  0  1.0   1  0  0  1
 -.500000000G0( 1 1, 2 1)
  F 12 -1
*
 HE    1S      2.    180  2  2  1  0  1  0
  1S/2S
 1S  1  0  0.0   1  0  1  1
 2S  2  0  1.0   1  0  1  1
 1.500000000G0( 1 1, 2 1)
  F 12 -1
*
 HE    3S      2.    180  2  2  1  0  1  0
  1S/2S
 1S  1  0  0.0   1  0  1  1
 2S  2  0  1.0   1  0  1  1
 -.500000000G0( 1 1, 2 1)
  F 12 -1
*
 HE    1S      2.    180  2  2  2  0  1  1  1  F  T
  1S/2S                  0.9965624
  1S2                      .114
 1S  1  0  0.0   1  0  1  1  2
 2S  2  0  1.0   1  0  1  1
 1.500000000G0( 1 1, 2 1)
 2.82842712 R0( 1 2 1, 1 1 2)
 -1.41421356L( 2 1, 1 2)
  F  9 -1 .3  0 1.D-7 .1D-6  T
*
C
C
C     IN THIS CASE, THE CONFIGURATIONS DIFFER BY EXACTLY ONE ELECTRON
C     AND THE INTERACTION NOW ALSO INVOLVES AN L INTEGRAL.   THE
C     CALCULATIONS HAVE BEEN SET UP IN SUCH A WAY THAT FIRST 1S, THEN
C     2S ARE IMPROVED  (IN THE MCHF CASE, 2S IS KEPT STRICTLY
C     ORTHOGONAL TO 1S), AFTER WHICH THE FUNCTIONS ARE ROTATED TO
C     SATISFY THE STATIONARY CONDITION, AND THE ENERGY MATRIX
C     DIAGONALIZED.   THE ROTATIONS SEEM TO INTRODUCE OSCILLATIONS
C     IN THIS CASE AND SO ACFG WAS SET TO 0.3 IN ORDER TO DAMP OUT
C     THESE OSCILLATIONS.
C
C
C     ------------------------------------------------------------------
C     2-6    E X A M P L E    6
C     -----------------------------------------------------------------
C
C     THIS EXAMPLE SHOWS HOW A SIXTH CONFIGURATION CAN BE ADDED TO AN
C     INTERACTION MATRIX, WHERE THE MATRIX WAS OUTPUT DURING A PREVIOUS
C     CALCULATION.  IT IS ASSUMED THAT RADIAL FUNCTIONS CAN BE READ
C     FROM UNIT 8.
C
  5  5  8  5
  9  0  9  9
 AR+2  3S     18.    200  6  0  6  2  3  6  0  F  F  1
 2P5/3P5                 0.9920873
 2S/3S                   0.0364112
 3S/3P5/3D(1P)           0.1149757
 3S/3P5/3D(3P)          -0.0348588
 3S/3P5/3D(3P)          -0.0015988
 2S/3P4/3D              -0.018
 1S  1  0  0.0   1  0 -1  2  2  2  2  2  2
 2S  2  0  3.0   1  0 -1  2  1  2  2  2  1
 2P  2  1  7.0   1  0 -1  5  6  5  5  5  6
 3S  3  0 10.0   1  0 -1  2  1  1  1  1  2
 3P  3  1 10.0   1  0 -1  5  6  5  5  5  4
 3D  3  2 12.0   3  0 -1  0  0  1  1  1  1
  0.12000000F2( 506, 506)
 -0.40000000F2( 506, 606)
  0.53333333G1( 506, 606)
 -0.08571429G3( 506, 606)
 -0.10000000G2( 606, 206)
  0.94280904R1( 6 3 6, 5 2 1)
 -1.63299316R1( 4 6 6, 5 5 2)
 -0.94280904R1( 4 3 6, 5 2 3)
  1.41421356R0( 4 3 6, 2 5 3)
 -0.81649658R0( 4 3 6, 2 5 4)
 -2.30940108R0( 4 3 6, 2 5 5)
  F  0  0  0  0 1.D-8 .1D-5
  -516.5748431
    -0.1543388  -513.0822716
    -0.2328091     0.1413721  -514.7085685
     0.1012540    -0.2399579    -0.2016125  -514.6445872
     0.0062108    -0.0069378    -0.0322798    -0.0086021  -515.0489374
*
C
C     NOTICE THAT THE DATA CARDS FOR THE ENERGY EXPRESSION NOW NEED
C     REFER ONLY TO THE NEW CONFIGURATION, ALL OTHER ENTRIES OF THE
C     INTERACTION MATRIX BEING KEPT FIXED.   THIS CAN BE USED TO
C     ADVANTAGE IN VERY LARGE PROBLEMS WHERE THE NUMBER OF FK, GK, OR
C     RK INTEGRALS MIGHT EXCEED THE MAXIMUM ALLOWED BY THE DIMENSIONS
C     OF THE ARRAYS.  IN THIS WAY ONE CAN, IN EFFECT, EVALUATE PORTIONS
C     OF THE MATRIX AT A TIME.
C
C
C     ------------------------------------------------------------------
C     2-7        P E R F O R M A N C E   T E S T   D A T A
C     ------------------------------------------------------------------
C
C
C     AN INDICATION OF THE ACCURACY OF THE NUMERICAL PROCEDURE USED IN
C     THIS PROGRAM IS GIVEN IN SEC. 6-9 AND ALSO COMPUT. PHYS. COMMUN.
C     4, 107 (1972).   THESE RESULTS ALL PERTAIN TO THE HYDROGENIC
C     PROBLEM.  ADDITIONAL SOURCES OF ERRORS ENTER INTO THE GENERAL HF
C     PROBLEM.  THE RESULTS FROM THE TEST DATA PROVIDED BELOW, INDICATE
C     THE LIMITS OF ACCURACY ON THE IBM 360/370 SERIES, AND ALSO PROVIDE
C     INFORMATION ABOUT THE RATE OF CONVERGENCE FOR OUR METHODS.  THE
C     CASES SELECTED  ARE TYPICAL TEST CASES OFTEN USED FOR EVALUATING
C     A METHOD.
C
C
  5  5  0  0
  0  0  0  0
 HE    1S      2.    150  1  1  1
  1S2
 1S  1  0  0.0   1  0  0  2
  F 10 10  0  0 .1D-9 .1D-9
*
 HE    1P      2.    180  2  2  1  0  1
  1S/2P
 1S  1  0  0.0   1  0  0  1
 2P  2  1  1.0   1  0  0  1
  0.50000000G1( 1 1, 2 1)
  F 10 10  0  0.1D-12.1D-12
*
 HE    3S      2.    180  2  2  1  0  1  0
  1S/2S
 1S  1  0  0.0   1  0  0  1
 2S  2  0  1.0   1  0  0  1
 -.500000000G0( 1 1, 2 1)
  F 12 -1  0  0 .1D-9 .1D-9
*
 HE    1S      2.    180  2  2  1  0  1  0
  1S/2S
 1S  1  0  0.0   1  0  1  1
 2S  2  0  1.0   1  0  1  1
 1.500000000G0( 1 1, 2 1)
  F 12 -1  0  0 .1D-9 .1D-9
*
 LI    4S      3.    200  3  3  1  0  3  0
  1S/2S/3S
 1S  1  0  0.0   1  0  0  1
 2S  2  0  1.0   1  0  0  1
 3S  3  0  2.0   1  0  0  1
 -.500000000G0( 1 1, 2 1)
 -.500000000G0( 1 1, 3 1)
 -.500000000G0( 2 1, 3 1)
  F 12 -1  0  0 .1D-9 .1D-9
*
 W+64  1S     74.    200  3  3  1
  1S2/2S2/2P6
 1S  1  0  0.0   1  0  0  2
 2S  2  0  2.0   1  0  0  2
 2P  2  1  7.0   1  0  0  6
  F 12 12  0  0.1D-11.1D-11
*
C
C
C     THE FOLLOWING  TABLE SUMMARIZES THE RESULTS.
C
C              T A B L E   OF   R E S U L T S
C
C          -E       - TOTAL ENERGY IN ATOMIC UNITS
C          PE/KE    - RATIO OF POTENTIAL AND KINETIC ENERGY
C          DPM      - MAXIMUM DIFFERENCE BETWEEN THE FUNCTIONS OF THE
C                     PREVIOUS AND CURRENT SCF ITERATION
C          NXCH     - NUMBER OF EXCHANGE FUNCTIONS COMPUTED
C
C
C                               -E         (PE/KE)+2   DPM      NXCH
C   1. HE  1S2 1S              2.861679995    4.D-9  1.38D-10  13( 8)
C   2. HE  1S/2P 1P            2.122464215    2.D-9  2.33D-14  19( 7)
C   3. HE  1S/2S 3S            2.174250777  -12.D-9  1.49D-08  18(12)
C   4. HE  1S/2S 1S            2.169854456   -1.D-9  7.37D-09  24(20)
C   5. LI  1S/2S/3S 4S         5.204454130  -16.D-9  4.29D-09  27(21)
C   6. W+64 1S2/2S2/2P6 1S 10318.516188029    1.D-9  2.00D-12  24(12)
C
C     THE METHODS USED IN THE PROGRAM RELY ON PROPERTIES OF THE HF
C     EQUATIONS, PARTICULARLY WHEN SATISFYING THE ORTHOGONALITY REQUIR-
C     EMENT.  THE DISCRETIZED APPROXIMATION WILL HAVE THESE PROPERTIES
C     ONLY TO LIMITED ACCURACY.  FOR EXAMPLE, THE DISCRETIZED PROBLEM
C     FOR HE 1S/2S 3S WITH OFF-DIAGONAL ENERGY PARAMTETERS EQUAL TO
C     ZERO, HAS SOLUTIONS FOR WHICH <1S!2S> = 1.4D-8.  THE ORTHOGON-
C     IZATION PROCESS THEN LIMITS THE APPARENT SCF CONVERGENCE.  HOW-
C     EVER, A SMALLER DPM DOES NOT NECESSARILY QUARANTEE GREATER ACC-
C     URACY.  A BETTER INDICATION OF ACCURACY IS THE RATIO, (PE/KE)+2,
C     WHICH FOR EXACT SOLUTIONS WOULD BE ZERO.  IN MOST CASES THE
C     MAGNITUDE OF THIS QUANTITY IS SEVERAL UNITS IN THE NINTH DECIMAL
C     PLACE.
C
C     AN INDICATION OF THE EFFECTIVENESS OF THE PROGRAM CAN BE OBTAINED
C     FROM THE NUMBER OF TIMES AN EXCHANGE FUNCTION HAS TO BE COMPUTED.
C     (IN LARGE ATOMS MOST OF THE COMPUTATION TIME IS DEVOTED TO THE
C     EVALUATION OF EXCHANGE FUNCTIONS, AND SO THIS IS A REASONABLY
C     CONVENIENT MACHINE INDEPENDENT MEASURE OF EFFICIENCY, WHERE THE
C     MOST EFFICIENT PROGRAM ACHIEVES A GIVEN ACCURACY WITH THE
C     LEAST AMOUNT OF COMPUTATION.)  THE FIRST NUMBER UNDER THE NXCH
C     COLUMN IS THE ACTUAL NUMBER OF CALLS TO XCH MADE BY THE PROGRAM,
C     BUT BECAUSE OF THE HIGH ACCURACY REQUESTED, SEVERAL OF THESE DID
C     NOT IMPROVE THE DEGREE OF SELF-CONSISTENCY.  IN PARENTHESES IS
C     THE NUMBER OF CALLS TO XCH REQUIRED FOR AN A POSTERIORI SELF-
C     CONSISTENCY OF AT LEAST 8.5D-8, WHERE THE DEGREE OF SELF-CONSIST-
C     ENCY IS NOW THE MAXIMUM DIFFERENCE BETWEEN THE CURRENT FUNCTION
C     AND ITS NEXT SCF ITERATE.  NOTICE THE VERY RAPID RATE OF CONVER-
C     GENCE FOR HIGHLY IONIZED SYSTEMS.  FOR W+64, AN AVERAGE OF 4.33
C     IMPROVEMENTS PER FUNCTION PRODUCED AN A POSTERIORI  DEGREE OF
C     SELF-CONSISTENCY OF AT LEAST 6.6D-9 .  A MORE DETAILED STUDY OF
C     THE RATE OF CONVERGENCE FOR THE VARIOUS CASES WILL APPEAR IN THE
C     JOURNAL OF COMPUTATIONAL PHYSICS, 1977.
C
C
▶EOF◀