Table 3.

Additional values of c_apq associated with multipole distribution representations of monatomic differential overlap distributions when interfragment quadrupole interactions are included

|pq〉	Index a	capq
|pxpx〉	2	−½
|pxpx〉	3	¼
|pxpx〉	4	−¼
|pxpy〉	1	¼
|pxpy〉	2	¼
|pxpy〉	3	−¼
|pxpy〉	4	−¼
|pxpz〉	1	¼
|pxpz〉	2	¼
|pxpz〉	3	−¼
|pxpz〉	4	−¼
|pypy〉	2	−½
|pypy〉	3	¼
|pypy〉	4	−¼
|pypz〉	1	¼
|pypz〉	2	¼
|pypz〉	3	−¼
|pypz〉	4	−¼
|pzpz〉	2	−½
|pzpz〉	3	¼
|pzpz〉	4	−¼

Including intermonomer quadrupole interactions will probably not be necessary in most cases. A study of 27 water dimers (10 of which were stationary points on the potential energy surface) showed that the sum of the quadrupole interactions consistently made up less than 0.5% of the total damped Coulomb interaction energy between the multipole charge distributions centered on the two oxygen atoms of each water dimer tested