1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
FUNCTION HELECT(N,P,H,F)
IMPLICIT DOUBLE PRECISION (A-H,O-Z)
DIMENSION P(*), H(*), F(*)
C***********************************************************************
C
C SUBROUTINE CALCULATES THE ELECTRONIC ENERGY OF THE SYSTEM IN EV.
C
C ON ENTRY N = NUMBER OF ATOMIC ORBITALS.
C P = DENSITY MATRIX, PACKED, LOWER TRIANGLE.
C H = ONE-ELECTRON MATRIX, PACKED, LOWER TRIANGLE.
C F = TWO-ELECTRON MATRIX, PACKED, LOWER TRIANGLE.
C ON EXIT
C HELECT = ELECTRONIC ENERGY.
C
C NO ARGUMENTS ARE CHANGED.
C
C***********************************************************************
ED=0.0D00
EE=0.0D00
K=0
NN=N+1
DO 20 I=2,NN
K=K+1
JJ=I-1
ED=ED+P(K)*(H(K)+F(K))
IF (I.EQ.NN) GO TO 20
DO 10 J=1,JJ
K=K+1
10 EE=EE+P(K)*(H(K)+F(K))
20 CONTINUE
EE=EE+.5D00*ED
HELECT=EE
RETURN
C
END
|
