<div dir="ltr"><div>Hello all,<br></div>I am trying to perform geometry optimizations using a hessian procedure with a smaller basis set, which then requires I use another procedure for the energy and gradient calculations (otherwise the hessian basis set becomes the default). The first point uses the analytic CCSD gradients, but after the hessian calculation numerical CCSD gradients are used. Have I specified one of my procedures incorrectly or is something more nefarious going on?<br>
Thanks,<br>Benj FitzPatrick<br><br>***,h2o<br>memory,150,M<br>gthresh,oneint=1.d-14,twoint=1.d-14,zero=1.d-14<br><br>oc2 = 1.400000<br><br>angstrom<br>symmetry,auto<br>geom={<br> c;<br> o, 1, oc2; <br>}<br>basis=avtz;<br>
{optg,root=1,energy=1.d-5,gradient=1.d-5,procedure=ccsdavtz,numhess=5,hessproc=b3lyphess}<br><br>proc ccsdavtz<br>hf;<br>ccsd;<br>endproc<br><br>proc b3lyphess<br>hf;<br>ks,b3lyp;<br>endproc<br><br></div>