Patent ID: 7343277

Claim:
A parallel computing method for transforming a 2-electron integration from an atomic-orbital base (rs|tu) to a molecular-orbital base (ab|cd) using a parallel computer having a plurality of processors, the method reducing an amount of computations by calculating at least three of the four indexes among (ab|cd) at the molecular orbital base, the method comprising: designating indexes r and s for the plurality of processors to calculate 2-electron integration (RS|tu) at the atomic orbital base, wherein designated indexes R and S indicate an atomic orbital allocated to a predetermined processor from the plurality of processors; performing processing for all combinations of designated indexes R and S and indexes t and u of the atomic orbital in parallel by the plurality of processors to calculate the at least three of the four indexes among (ab|cd) at the molecular orbital base; and storing the at least three of the four calculated indexes among (ab|cd) at the molecular orbital base in a memory.