<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px"><div id="yiv7192667509"><div id="yui_3_16_0_1_1421105564285_5057"><div id="yui_3_16_0_1_1421105564285_5056" style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px;"><br clear="none"><div id="yiv7192667509yui_3_16_0_1_1421105564285_3840" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px;"><div id="yiv7192667509yui_3_16_0_1_1421105564285_3839" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px;"><div class="yiv7192667509y_msg_container" id="yiv7192667509yui_3_16_0_1_1421105564285_3838">Dear Molpro experts,<div id="yiv7192667509"><div id="yiv7192667509yui_3_16_0_1_1421105564285_3837"><div id="yiv7192667509yui_3_16_0_1_1421105564285_3836" style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px;"><div id="yiv7192667509"><div id="yiv7192667509yui_3_16_0_1_1421019687926_3267" style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px;"><div id="yiv7192667509"><div id="yiv7192667509yui_3_16_0_1_1420872212154_9130" style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px;"><div id="yiv7192667509"><div id="yiv7192667509yui_3_16_0_1_1420872212154_8097" style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, Sans-Serif;font-size:16px;"><div id="yiv7192667509yui_3_16_0_1_1420872212154_7075"><br clear="none"></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_7073"><div id="yiv7192667509yui_3_16_0_1_1420872212154_8123"><div id="yui_3_16_0_1_1421105564285_5204" dir="ltr">Please accept my apologies for my long message. I try to be as concise as possible.   <br></div><div id="yui_3_16_0_1_1421105564285_5206"><br></div><div id="yui_3_16_0_1_1421105564285_5208">I`m trying to calculate the excitation energies (EEs) of a diatomic molecule (FeAg) using the Molpro and ORCA quantum chemistry packages. What I`m willing to obtain is "identical" excitation energies with these two codes. Despite the slight, at least in my opinion, differences in the SA-CASSCF optimization algorithms implemented in these two codes (e.g.,</div></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_8119">1) CSF-based optimization of ORCA Vs determinant-based optimization of Molpro in SA-CASSCF calculations<br clear="none"></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_8121"><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9359">2) non-linear coupled optimization of molpro (Werner) Vs uncoupled optimizations (Newton-Rouphson, DIIS, ...) of ORCA</div></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_8125">.</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_8166">.</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_8168">.)</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_8170"><br clear="none"></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_8172"><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9191"><div id="yiv7192667509yui_3_16_0_1_1421105564285_3972">I`m employing identical basis sets, active spaces, inactive (closed) spaces, etc in these two programs. Thus, I think expecting identical results (either energy deference or absolute energies) might be totally warranted. <br clear="none"></div><div id="yiv7192667509yui_3_16_0_1_1421105564285_3973"><br clear="none"></div><div id="yiv7192667509yui_3_16_0_1_1421105564285_3974">The thing is this is the case "just" for a CAS space of (9e,7o) spanned by the atomic {molecular} representations (4s3d^Fe) and (5s^Ag) {sig(3), delta, and pi}, i.e., using this active space, these two codes give identical EEs and absolute energies. However, when the full valence space of (19e,12o), consisting of (4s3d^Fe) and (5s4d^Ag) {sig(4), delta (2), and pi(2)} which is a more adequate/realistic one, is used the Molpro results show considerably different EEs from those of ORCA. I need to confess that these differences which is about 2500 cm^-1 (at the worst case) cannot be considered "huge" but closer results are required for the system at hand.</div><div id="yiv7192667509yui_3_16_0_1_1421105564285_4062"><br clear="none"></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1421105564285_4043">I think, basically, these discrepancies between EEs of the two codes is due to the following compositions of natural MOs (in irrep A_1) optimized at the CAS(19e,12o) level of theory (from 15.1 to 20.1 is active):</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1421105564285_4097"> Orb     Occ        Energy       Coefficients</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1421105564285_4154">++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++<br class="yiv7192667509" style="" clear="none"><br class="yiv7192667509" style="" clear="none">                                                     1 1s      1 1s      1 1s      1 1s      1 1s      1 1s      1 1s      1 1s      1 1s      1 1s   <br class="yiv7192667509" style="" clear="none">                                                     1 1s      1 1s      1 1s      1 1s      1 2pz     1 2pz     1 2pz     1 2pz     1 2pz     1 2pz  <br class="yiv7192667509" style="" clear="none">                                                     1 2pz     1 2pz     1 2pz     1 2pz     1 3d0     1 3d2+    1 3d0     1 3d2+    1 3d0     1 3d2+ <br class="yiv7192667509" style="" clear="none">                                                     1 3d0     1 3d2+    1 3d0     1 3d2+    1 4f0     1 4f2+    1 4f0     1 4f2+    1 4f0     1 4f2+ <br class="yiv7192667509" style="" clear="none">                                                     1 5g0     1 5g4+    1 5g2+    2 1s      2 1s      2 1s      2 1s      2 1s      2 1s      2 1s   <br class="yiv7192667509" style="" clear="none">                                                     2 1s      2 1s      2 1s      2 1s      2 1s      2 2pz     2 2pz     2 2pz     2 2pz     2 2pz  <br class="yiv7192667509" style="" clear="none">                                                     2 2pz     2 2pz     2 2pz     2 2pz     2 3d0     2 3d2+    2 3d0     2 3d2+    2 3d0     2 3d2+ <br class="yiv7192667509" style="" clear="none">                                                     2 3d0     2 3d2+    2 3d0     2 3d2+ <br class="yiv7192667509" style="" clear="none">  14.1  2.00000    -0.502146    -0.001015 -0.000011 -0.000088 -0.000423 -0.001134  0.000337  0.004706  0.006334 -0.002624 -0.014412<br class="yiv7192667509" style="" clear="none">                                                    -0.011738  0.002893  0.090524 -0.033874  0.003529  0.000112  0.000271 -0.002368 -0.007818 -0.001503<br class="yiv7192667509" style="" clear="none">                                                    -0.007113  0.037722  0.036990 -0.018287  0.007173  0.000000  0.006388  0.000000  0.000198  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.024728  0.000000 -0.004631  0.000000  0.000080  0.000000  0.000223  0.000000  0.002026  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.000075  0.000000  0.000000 -0.000033 -0.000004 -0.000017  0.000296  0.000680 -0.000543 -0.001423<br class="yiv7192667509" style="" clear="none">                                                     0.001182 -0.001467  0.004694 -0.002035 -0.035825  0.000509  0.000045 -0.000310 -0.002299  0.003527<br class="yiv7192667509" style="" clear="none">                                                    -0.005320  0.011943 -0.011928  0.043778 -0.253219  0.000000  0.010008  0.000000  0.370894  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.493947  0.000000  0.310074  0.000000<br class="yiv7192667509" style="" clear="none"><br class="yiv7192667509" style="" clear="none">  15.1  2.00000    -0.498811     0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.000000  0.000000  0.000000  0.000000  0.000000  0.000815  0.000000 -0.000031  0.000000  0.001877<br class="yiv7192667509" style="" clear="none">                                                     0.000000 -0.003179  0.000000  0.013680  0.000000  0.000047  0.000000 -0.000177  0.000000  0.001064<br class="yiv7192667509" style="" clear="none">                                                     0.000000  0.000000  0.000021  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.000000  0.000000  0.000000  0.000000  0.000000 -0.254068  0.000000  0.010335  0.000000  0.375990<br class="yiv7192667509" style="" clear="none">                                                     0.000000  0.494604  0.000000  0.320878<br class="yiv7192667509" style="" clear="none"><br class="yiv7192667509" style="" clear="none">  16.1  1.99873    -2.707087    -0.000010  0.000000 -0.000001 -0.000009 -0.000011 -0.000013  0.000187  0.000148  0.000024 -0.001313<br class="yiv7192667509" style="" clear="none">                                                     0.000525 -0.000108  0.001382  0.000143  0.325725  0.004979  0.020291 -0.245961 -0.476994 -0.390804<br class="yiv7192667509" style="" clear="none">                                                    -0.094062  0.000806 -0.001811  0.000502  0.000440  0.000000  0.000508  0.000000 -0.000169  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.000107  0.000000  0.000089  0.000000  0.000020  0.000000  0.000058  0.000000 -0.000115  0.000000<br class="yiv7192667509" style="" clear="none">                                                    -0.000008  0.000000  0.000000 -0.000048 -0.000007 -0.000019  0.000164  0.000127  0.000039 -0.000312<br class="yiv7192667509" style="" clear="none">                                                    -0.000632  0.000584  0.000997 -0.000840 -0.001190 -0.000553 -0.000036  0.000598  0.001010  0.000225<br class="yiv7192667509" style="" clear="none">                                                    -0.001080 -0.002101 -0.000195  0.000712 -0.001950  0.000000  0.000078  0.000000  0.002893  0.000000<br class="yiv7192667509" style="" clear="none">                                                     0.003809  0.000000  0.002121  0.000000</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1421105564285_4233">...<br clear="none"></div><div class="yiv7192667509" id="yiv7192667509yui_3_16_0_1_1421105564285_3974" style=""><div dir="ltr"> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</div></div></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9315"><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1421105564285_4156"><div id="yui_3_16_0_1_1421105564285_5358" dir="ltr">These compositions show that the optimized reference space is spanned by 15.1 (4d^Ag), 16.1 (2p^Fe) ... and the 14.1(4d^Ag) is turned out to be a core orbital whereas it is expected to have this orbital in the active space! The same happens for B_1 and B_2 irreps. <br></div><div id="yui_3_16_0_1_1421105564285_5368" dir="ltr"><br></div><div id="yui_3_16_0_1_1421105564285_5393" dir="ltr">This is my input by the way:</div><div id="yui_3_16_0_1_1421105564285_5503" dir="ltr"><br> </div><div class="qtdSeparateBR"><br><br></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd69157"><div id="yui_3_16_0_1_1421105564285_5400" dir="ltr"> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</div><div id="yui_3_16_0_1_1421105564285_5455" dir="ltr">   SET,DKROLL=1<br style="" class=""> <br style="" class="">   {rhf<br style="" class="">   wf,73,4,5;<br style="" class="">  occ,20,8,8,3;<br style="" class="">  closed,17,7,7,2<br style="" class="">  orbital,2100.2<br style="" class="">  }<br style="" class=""> <br style="" class="">  {casscf;occ,20,8,8,3;closed,16,7,7,2<br style="" class=""> { ITERATIONS;<br style="" class=""> DO,internal,2,TO,20;<br style="" class=""> }<br style="" class="">    start,2100.2;<br style="" class="">    WF,73,1,3;state,3<br style="" class="">    WF,73,2,3;state,3<br style="" class="">    WF,73,3,3;state,3<br style="" class="">    WF,73,4,3;state,3<br style="" class="">    WF,73,1,5;state,3<br style="" class="">    WF,73,2,5;state,3<br style="" class="">    WF,73,3,5;state,3<br style="" class="">    WF,73,4,5;state,3<br style="" class="">  expec2,lxx,lyy,lzz;<br style="" class="">  natorb,ci,print;<br style="" class="">  ORBITAL,2140.2;<br style="" class="">   }<br style="" class=""> <br style="" class="">  {casscf;occ,20,8,8,3;closed,14,6,6,1<br style="" class=""> { ITERATIONS;<br style="" class=""> DO,internal,2,TO,20;<br style="" class=""> }<br style="" class="">     start,2140.2;<br style="" class="">    WF,73,1,3;state,3<br style="" class="">    WF,73,2,3;state,3<br style="" class="">    WF,73,3,3;state,3<br style="" class="">    WF,73,4,3;state,3<br style="" class="">    WF,73,1,5;state,3<br style="" class="">    WF,73,2,5;state,3<br style="" class="">    WF,73,3,5;state,3<br style="" class="">    WF,73,4,5;state,3<br style="" class="">  expec2,lxx,lyy,lzz;<br style="" class="">  natorb,ci,print;<br style="" class="">  ORBITAL,2140.2;<br style="" class="">   }<br></div><div id="yui_3_16_0_1_1421105564285_5401" style="" class="" dir="ltr"> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</div><div id="yui_3_16_0_1_1421105564285_5401" style="" class="" dir="ltr"><br style="" class="" clear="none"></div></div></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd53399"><div class="yiv7192667509" dir="ltr" id="yiv7192667509yui_3_16_0_1_1421105564285_4156" style=""> </div></div></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd59205"><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9317">Could someone help me about this problem please?<br clear="none"></div><br><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9554"><br clear="none"></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9589"><br clear="none"></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9591"><br clear="none"></div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9360">Thanks a lot in advance,</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9362">sincerely yours.</div><div dir="ltr" id="yiv7192667509yui_3_16_0_1_1420872212154_9364">Davood.  </div></div></div></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd67365"><div id="yiv7192667509yui_3_16_0_1_1420872212154_7071"><br clear="none"></div></div></div></div></div></div></div></div></div></div></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd70707"><br clear="none"><br clear="none"></div></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd69119"> </div></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd96330"> </div></div><div class="yiv7192667509yqt3959764669" id="yiv7192667509yqtfd07037">  </div></div></div></div></div></body></html>