摘 要: | The divergence in SCF iterative process of quantum chemistry is the most common source of dif-ficulty for the calculations such as ab initio, INDO, CNDO, etc. We propose a new iterative formula call-ed "Diagonal Shift Formula" (DSF), and give its theoretical ptoOf. ln' Practice. Lundreds of mole-cules, laIge and small, and even the ones with unreasonable structures, have all successfully converged inat most l5 iterative steps. Thus the DSF metkod kas been proved to possess the general convergent capac-ity and fine numerical stability both in mathematics and practice. By CNDO we bave succe'sfully cal-culatcd the largest molecule in China, and the most important biomoIecu1e ATP which was once re-ported never converged. Both molecu1es have converged smoQthly by DSP method.
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