level

weights

R

Lmax

BS (Å)

BP (Å)

               

1

Savin

16

13

-

-

1040

5.3´ 104

2

Savin

32

19

-

-

3414

1.3´ 104

3

Becke

41

31

6

6

9512

1.3´ 105

4

Becke

52

52

9

9

34586

1.3´ 106

               

 

Table 2 - Values of internal variables for each level of accuracy in the total energy and DFT matrix element integrations (computational parameters 1 and 2). The weights column denotes whether Savin or Becke weights are used in the atomic partitioning, R is the number of points used in the radial integration, Lmax is the maximum degree of angular polynomial that may be exactly integrated, BS and BP are the cutoff radii for sums and products of Becke weights respectively. is the number of grid points per atom and is the relative error in the integrated charge, both averaged in the mean over the eighteen test systems.