<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:14px"><div id="yui_3_16_0_1_1457457550332_4594">Dear molpro users,<br></div><div id="yui_3_16_0_1_1457457550332_4925"><br></div><div id="yui_3_16_0_1_1457457550332_4926">I want to perform CCSD calcuation for fenchone molecule using relatively large basis sets</div><div dir="ltr" id="yui_3_16_0_1_1457457550332_4719">cc-pVTZ for C and H atoms and t-aug-cc-pVTZ for O atom. I have used the largest meomery</div><div id="yui_3_16_0_1_1457457550332_4911" dir="ltr">which is avaiavle in our cluster. But, this calcuation still needs more memory. Now, my question is <br></div><div id="yui_3_16_0_1_1457457550332_4912" dir="ltr">that is there any way to overcome this problem using for e.g an appromxiation method which allows <br></div><div id="yui_3_16_0_1_1457457550332_4969" dir="ltr">to run this calcuation without problem?</div><div id="yui_3_16_0_1_1457457550332_5012" dir="ltr"><br></div><div id="yui_3_16_0_1_1457457550332_5013" dir="ltr">Thank you very much in advance for your help<br></div><div id="yui_3_16_0_1_1457457550332_4913" dir="ltr"><br></div><div id="yui_3_16_0_1_1457457550332_4884" dir="ltr">This is my input:</div><div id="yui_3_16_0_1_1457457550332_4914" dir="ltr"><br></div><div id="yui_3_16_0_1_1457457550332_4915" dir="ltr">***,fenchone CCSD!<br>{memory,100000,m}<br>gprint,basis<br>gexpec,dm,sm,qm<br>!<br>basis={C=cc-pVTZ;H=cc-pVTZ;O=t-aug-cc-pVTZ}<br>geomtyp=xyz<br>geometry={<br>27<br>geometry input<br> O , 2.52970, 0.38020, 1.47680<br> C ,-0.00430,-1.22180, 2.23870<br> C , 0.08010, 0.13640, 1.50670<br> C ,-0.17180, 1.24990, 2.53740<br> C , 1.48290, 0.29150, 0.86900<br> C , 2.56330, 0.02430,-1.44260<br> C , 1.30210, 0.32480,-0.65290<br> C ,-0.81640, 1.56820,-0.41490<br> C , 0.64650, 1.72070,-0.93530<br> C ,-0.81180, 0.15900, 0.22540<br> C , 0.06770,-0.60030,-0.79900<br> H ,-0.97930,-1.32250, 2.73060<br> H , 0.12180,-2.07670, 1.56710<br> H , 0.77570,-1.28140, 3.00480<br> H ,-1.18590, 1.17540, 2.94880<br> H , 0.54140, 1.15220, 3.36210<br> H ,-0.04800, 2.25300, 2.11900<br> H , 2.92940,-0.98710,-1.23330<br> H , 2.38290, 0.10720,-2.52080<br> H , 3.36260, 0.72190,-1.17070<br> H ,-1.11110, 2.36140, 0.27670<br> H ,-1.52850, 1.59220,-1.24710<br> H , 0.67390, 1.91530,-2.01370<br> H , 1.19500, 2.53440,-0.44830<br> H ,-1.81180,-0.25320, 0.39360<br> H ,-0.35010,-0.58040,-1.81250<br> H , 0.27670,-1.64230,-0.53650<br>}<br>hf<br>ccsd<br>save,files<br>eom,-10.1<br>show,energy<br>set,state= [' 1.1',' 2.1',' 3.1',' 4.1',' 5.1',' 6.1',' 7.1',' 8.1',' 9.1',' 10.1']<br><br></div></div></body></html>