<div>Manuel,</div> <div> </div> <div>Which version of the libint library are you using? Had some trouble compiling 1.1.3 </div> <div>Thanks, </div> <div>On 7/30/07, mguidon <<a href="mailto:manuel...@gmail.com">manuel...@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"> Hi. The HSE functional is a hybrid functional. It consists of screened exact Hartree-Fock exchange and two GGA-functionals (PBE and hole- averaged screened PBE functional). The keywords are (see /tests/QS/ regtest-hybrid/NE-hybrid-HSE06-lda.inp): &XC_FUNCTIONAL &XWPBE SCALE_X -0.25 SCALE_X0 1.0 OMEGA 0.11 &END &PBE SCALE_X 0.0 SCALE_C 1.0 &END PBE &END XC_FUNCTIONAL &HF EPS_SCHWARZ 1.0E-10 MAX_MEMORY 10 FRACTION 0.25 SCREENING_TYPE SHORTRANGE OMEGA 0.11 &END As in the case of B3LYP the functional is quite expensive since exact exchange has to be calculated. However, the keyword OMEGA decreases the cost for the Hartree-Fock part because it results in a better screening. To get accurate results it is recommended to use OMEGA values within the range of 0.1 and 0.2. (Higher value means better screening means faster execution). In the current version, analytical derivatives up to second order are implemented which means that forces/ stresses are available. As with all calculations including Hartree-Fock exchange you need an up-to-date g95 compiler together with the libint-library in order to run cp2k. Cheers Manuel Guidon Reston, VA 443-567-8328 (C) 410-278-2692 (O)