<div dir="ltr"><div><div><div><div>Hi<br></div><div>Â I have a couple of questions.<br><br></div>1)
I am calculating optimization and frequency calculation of benzene.
After optimization when I calculate the single point energy calculation
the SP energy is lower than the optimized energy. I am taking the
optimized Z matrix to run the SP energy calculation. How it is possible?
What I am missing? Here I am giving my input of optimization and output
files of both SP and optimization calculations.<br><br></div><div>Optimization input<br></div><div><br> ***,coupling constants<br> memory,450,m<br> cc2   =   1.394207,<br> ccc3  =   120.000,<br> dih4  =     0.000,<br> hc7   =   1.082115,<br> dih7  =   180.000<br> basis,avtz<br> geomtype = zmat<br> geometry = {angstrom,<br> c;<br> c,  1, cc2;<br> c,  2, cc2,       1, ccc3;<br> c,  3, cc2,       2, ccc3,         1, dih4;<br> c,  4, cc2,       3, ccc3,         2, dih4;<br> c,  5, cc2,       4, ccc3,         3, dih4;<br> h,  2, hc7,       3, ccc3,         4, dih7;<br> h,  3, hc7,       2, ccc3,         1, dih7;<br> h,  4, hc7,       3, ccc3,         2, dih7;<br> h,  5, hc7,       4, ccc3,        3, dih7;<br> h,  6, hc7,       5, ccc3,        4, dih7;<br> h,  1, hc7,       2, ccc3,        3, dih7;<br> }<br> {hf,ENERGY=1.0E-10,orbital=1.0E-8;}<br> {df-hf,ENERGY=1.0E-10,orbital=1.0E-8;}<br> {df-mp2,ENERGY=1.0E-10,orbital=1.0E-8;}<br> optg;<br> frequencies;<br></div><div><br></div><div>SP energy input<br><br>! Cite this work as:<br> ***,coupling constants<br> memory,450,m<br>cc2   =   1.394247,<br>cc3   =   1.394247,<br>ccc3  =   120.000,<br>cc4   =   1.394247,<br>ccc4  =   120.000,<br>dih4  =     0.000,<br>cc5   =   1.394247,<br>ccc5  =   120.000,<br>dih5  =     0.000,<br>cc6   =   1.394247,<br>ccc6  =   120.000,<br>dih6  =     0.000,<br>hc7   =   1.082198,<br>hcc7  =   120.000,<br>dih7  =   180.000,<br>hc8   =   1.082198,<br>hcc8  =   120.000,<br>dih8  =   180.000,<br>hc9   =   1.082198,<br>hcc9  =   120.000,<br>dih9  =   180.000,<br>hc10  =   1.082198,<br>hcc10 =   120.000,<br>dih10 =   180.000,<br>hc11  =   1.082198,<br>hcc11 =   120.000,<br>dih11 =   180.000,<br>hc12  =   1.082198,<br>hcc12 =   120.000,<br>dih12 =   180.000<br>basis,avtz<br>!gprint,orbitals,civectors<br> geomtype = zmat<br> geometry = {angstrom,<br>c;<br>c,  1, cc2;<br>c,  2, cc3,       1, ccc3;<br>c,  3, cc4,       2, ccc4,         1, dih4;<br>c,  4, cc5,       3, ccc5,         2, dih5;<br>c,  5, cc6,       4, ccc6,         3, dih6;<br>h,  3, hc7,       2, hcc7,         1, dih7;<br>h,  4, hc8,       3, hcc8,         2, dih8;<br>h,  5, hc9,       4, hcc9,         3, dih9;<br>h,  6, hc10,      5, hcc10,        4, dih10;<br>h,  1, hc11,      2, hcc11,        3, dih11;<br>h,  2, hc12,      3, hcc12,        4, dih12;<br>}<br>{hf,ENERGY=1.0E-10,orbital=1.0E-8;}<br>{df-hf,ENERGY=1.0E-10,orbital=1.0E-8;}<br>{df-mp2,ENERGY=1.0E-10,orbital=1.0E-8;}<br><br><br></div>2)
In the frequency (numerical) calculation, it distort the molecule to
get Hessian. I want the forces at each displacement.
When I check the output files, it is not wring the information. How can I
get the information?<br><br></div>I look forward to hear from you<br><br></div>Thank you</div>