<div>Hi,</div>
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<div> I am trying to calculate the MRCI dipole moment for stretching one of the CH bonds for linear acetylene (HCCH). As I stretch one of the CH bonds, the dipole moment increases from 0 to 0.38 debye at 1.8 Angstroms, and decreases to -
0.65 Angstroms at around 3.2 Angstroms. This clearly can't be correct since the dipole moment of the CCH radical at the same level of theory is 0.7 Debye (all molecules are oriented in the same direction so the change in dipole moment sign is very incorrect). Does anyone know what is wrong? I have included a sample input for the
2.2 Angstrom case.</div>
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<div>Bryan</div>
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<div>CC=1.21120500<br>H1C2=2.2<br>H2C1=1.06408640</div>
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<p>geometry={;ang;noorient;<br>C1<br>C2,C1,CC<br>X1,C2,1.00,C1,90.0<br>H1,C2,H1C2,X1,90.0,C1,180.0<br>X2,C1,1.00,C2,90.0,X1,180.0<br>H2,C1,H2C1,X2,90.0,C2,180.0};</p>
<p>basis<br> default=aug-cc-pvqz<br>end</p>
<p>rhf<br>mcscf<br>mrci<br>optg;inactive,H1C2</p></div>