<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div>Hi,</div><div><br></div><div>I would like to ask how Molpro calculate quadrupole moment at the origin. I need get the value of charge for certain r (distance between charges) for each transition. I know how to do it using dipole moment, but I am confused a little with quadrupole moment. For example in a case of RHF calculations I get output:</div> <br>Dipole moment /Debye 3.66434903 -3.50862417 0.00000000<br><br> !RHF expec <1.1|XX|1.1> -35.258672915978<br> !RHF expec <1.1|YY|1.1>
-40.017295422307<br> !RHF expec <1.1|ZZ|1.1> -34.966530874802<br> !RHF expec <1.1|XY|1.1> -6.812741388569<br><br> !RHF expec <1.1|QMXX|1.1> 2.233240232577<br> !RHF expec <1.1|QMYY|1.1> -4.904693526919<br> !RHF expec <1.1|QMZZ|1.1> 2.671453294341<br> !RHF expec <1.1|QMXY|1.1> -10.219112082854<br> !RHF expec <1.1|QMRR|1.1> -110.242499213091<br><br><div>What is the
difference between <1.1|XX|1.1> and <1.1|QMXX|1.1>.</div><div><br></div><div>Best wishes,</div><div><br></div><div>Lilianna<br></div><div></div></div></body></html>