<br><div>Dear all, <br></div><div><br></div><div>I am computing a single energy qm/mm, which contains a Zn ion in the qm part. From the Mulliken charges I obtained the next results:</div><div><br></div><div>Does it make sense to obtain a negative net charge for Zn?</div><div><br></div><div>Thank you in advance.</div><div>Manuel<br></div><div><br></div><div><br></div><div><br></div><div> !-----------------------------------------------------------------------------!<br>                     Mulliken Population Analysis<br><br> #  Atom  Element  Kind  Atomic population (alpha,beta) Net charge  Spin moment<br>       1     S        1         3.021457     3.021457    -0.042914     0.000000<br>       2     S        1         2.928958     2.928958     0.142084     0.000000<br>       3     S        1         2.986412     2.986412     0.027176     0.000000<br>       4     N        2         2.565672     2.565672    -0.131343     0.000000<br>       5     N        2         2.485414     2.485414     0.029171     0.000000<br>       6     O        3         3.109528     3.109528    -0.219056     0.000000<br>       7     O        3         3.105392     3.105392    -0.210783     0.000000<br>       8     C        4         2.150279     2.150279    -0.300557     0.000000<br>       9     C        4         2.160257     2.160257    -0.320514     0.000000<br>      10     C        4         2.174493     2.174493    -0.348986     0.000000<br>      11     C        4         1.948747     1.948747     0.102507     0.000000<br>      12     C        4         2.020464     2.020464    -0.040929     0.000000<br>      13     C        4         1.953054     1.953054     0.093892     0.000000<br>      14     C        4         2.120215     2.120215    -0.240430     0.000000<br>      15     H        5         0.445247     0.445247     0.109506     0.000000<br>      16     H        5         0.443358     0.443358     0.113285     0.000000<br>      17     H        5         0.423839     0.423839     0.152322     0.000000<br>      18     H        5         0.476071     0.476071     0.047857     0.000000<br>      19     H        5         0.470147     0.470147     0.059707     0.000000<br>      20     H        5         0.465764     0.465764     0.068471     0.000000<br>      21     H        5         0.460301     0.460301     0.079397     0.000000<br>      22     H        5         0.455960     0.455960     0.088080     0.000000<br>      23     H        5         0.473664     0.473664     0.052673     0.000000<br>      24     H        5         0.471544     0.471544     0.056912     0.000000<br>      25     H        5         0.463696     0.463696     0.072607     0.000000<br>      26     H        5         0.462198     0.462198     0.075605     0.000000<br>      27     H        5         0.467569     0.467569     0.064862     0.000000<br>      28     ZN       6         6.421314     6.421314    -0.842628     0.000000<br>      29     H        7         0.461432     0.461432     0.077135     0.000000<br>      30     H        7         0.468804     0.468804     0.062392     0.000000<br>      31     H        7         0.469881     0.469881     0.060237     0.000000<br>      32     H        7         0.468868     0.468868     0.062264     0.000000<br> # Total charge and spin       49.000000    49.000000    -1.000000     0.000000<br><br></div>