<div dir="ltr"> <style type="text/css"> p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Menlo; color: #000000; background-color: #fefeec} span.s1 {font-variant-ligatures: no-common-ligatures} </style> <p class="p1"><font face="arial, sans-serif"><span style="font-variant-ligatures: no-common-ligatures;">Dear community, </span></font></p><p class="p1"><font face="arial, sans-serif"><span style="font-variant-ligatures: no-common-ligatures;"><br></span></font></p><p class="p1"><font face="arial, sans-serif"><span style="font-variant-ligatures: no-common-ligatures;">I am running a simulation of a sodium aluminate (NaAlO2) crystal, orthorombic, and since I will need to obtain core-level spectroscopy results I am running this system with GAPW and all-electron scheme. </span></font></p><p class="p1"><font face="arial, sans-serif"><span style="font-variant-ligatures: no-common-ligatures;"><br></span></font></p><p class="p1"><font face="arial, sans-serif"><span style="font-variant-ligatures: no-common-ligatures;">Unfortunately, I keep getting the following error at the very beginning of the SCF, using OT or diagonalization, with any preconditioning scheme:</span></font></p><p class="p1"><br></p><p class="p1"><font face="arial, sans-serif"><b><span class="s1">Cholesky decompose failed: the matrix is not positive definite or </span><span style="font-variant-ligatures: no-common-ligatures;">ill-conditioned.</span><span class="Apple-converted-space" style="font-variant-ligatures: no-common-ligatures;"> </span></b></font></p><p class="p1"><font face="arial, sans-serif"><b><span class="Apple-converted-space" style="font-variant-ligatures: no-common-ligatures;"><br></span></b></font></p><p class="p1"><font face="arial, sans-serif"><span style="font-variant-ligatures: no-common-ligatures;">I have tried the following basis sets:</span></font></p><p class="p1"><font face="arial, sans-serif"><span style="font-variant-ligatures: no-common-ligatures;"><br></span></font></p><p class="p1"><span class="s1">OK: 3-21Gx</span></p><p class="p1"><span class="s1">6-31Gx</span></p><p class="p1"><span class="s1">6-31Gxx</span></p><p class="p1"><span class="s1">6-31++Gxx</span></p><p class="p1"><span class="s1">6-311Gxx</span></p><p class="p1"><span class="s1">6-311++G2d2p <span class="Apple-converted-space"> </span></span></p><p class="p1"><span class="s1">6-311++G3df3pd<span class="Apple-converted-space"> </span></span></p><p class="p1"><span class="s1">OK: Ahlrichs-VDZ</span></p><p class="p1"><span class="s1">OK: Ahlrichs-VTZ</span></p><p class="p1"><span class="s1">OK: Ahlrichs-pVDZ</span></p><p class="p1"><span class="s1">Ahlrichs-TZV</span></p><p class="p1"><span class="s1">Ahlrichs-pTZV</span></p><p class="p1"><span class="s1">Roos-ADZ-ANO</span></p><p class="p1"> <style type="text/css"> p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Menlo; color: #000000; background-color: #fefeec} span.s1 {font-variant-ligatures: no-common-ligatures} </style> </p><p class="p1"><span class="s1">Roos-ATZ-ANO</span></p><p class="p1"><span class="s1"><br></span></p><p class="p1"><span class="s1">and I get the error for ALL of them excepted the ones preceded by "OK:" in the list. </span></p><p class="p1"><span class="s1">The error is persisting both slightly randomizing the coordinates or with a 2x2x2 supercell.</span></p><p class="p1"><span class="s1"><br></span></p><p class="p1"><span class="s1">Attached input file and coordinates. Without preconditioning it works, but with extremely difficult convergence. A wavefunction from the non-preconditioned run can be used as a GUESS, but when preconditioning is switched on, the error appears again.</span></p><p class="p1"><span class="s1"><br></span></p><p class="p1"><span class="s1">Any help with this is appreciated. Thank you.</span></p><p class="p1"><span class="s1">Best regards, </span></p><p class="p1"><span class="s1"><br></span></p><p class="p1"><span class="s1">Daniele Passerone</span></p><p class="p1"><span class="s1"><br></span></p><p class="p1"><span class="s1"><br></span></p></div>