Efficient Evaluation of Two-Center Gaussian Integrals in Periodic Systems

Evaluation of Two-Center, Two-Electron Integrals.

We present a new analytic treatment of two-electron integrals over two-center integrals including correlation (interelectronic distance) explicitly in the wave function. All the integrals needed for the evaluation of the matrix elements of any diatomic two-electron molecule are obtained as analytic recursion expressions. As an application of this method in molecular physics, we calculate the va...

Rapid evaluation of two-center two-electron integrals

We present optimal formulae for two-center two-electron replusion integrals (ERIs) over Cartesian Gaussian basis functions. Floating-point operations (flop) counts reveal that two-center ERIs are often an order of magnitude cheaper than their four-center analogues. c © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 1505–1510, 2000

Efficient calculation of integrals in mixed ramp-Gaussian basis sets.

Algorithms for the efficient calculation of two-electron integrals in the newly developed mixed ramp-Gaussian basis sets are presented, alongside a Fortran90 implementation of these algorithms, RampItUp. These new basis sets have significant potential to (1) give some speed-up (estimated at up to 20% for large molecules in fully optimised code) to general-purpose Hartree-Fock (HF) and density f...

evaluation of sadr eminence in safavid period

چکیده: یکی از دوره های مهم تاریخی ایران به لحاظ تأمین استقلال ملی مذهبی و حتی تأثیر آن بر فرهنگ و مذهب ایرانیان، دوره صفویه است. رسمیت دادن و رواج مذهب شیعه توسط شاه اسماعیل اول، یکی از مهمترین اقدامات این دولت محسوب می شود. بنابراین برای اجرای این سیاست، وی منصب صدارت را به عنوان منصبی مذهبی- حکو متی ایجاد کرد .این منصب از دوره ی تیموریان ایجاد شده بود ولی در اواخر این دوره اهمیت بیشتری یافت...

Gaussian integrals