<HTML><BODY>Hello, molpro users.<br><br>Is there any possibility to calculate the root mean square (r.m.s.)<br>distance of the outermost electron of a particular atom with the help of molpro2010 package?<br>I faced several problems, when I tried to do it. Here they are:<br><br>1) How can one get the wave function of the outermost electron?<br>Is it possible in molpro to extract a wave function of a particular electron from the wave function of the atom?<br>In other words, can I take in molpro2010 one-electron wave function (with the desired set of quantum numbers n,l,m)<br>from a Slater determinant after restricted/unrestricted-HF routine for an atom?<br><br>2) So, I should calculate the diagonal matrix element of the x^2+y^2+z^2=r^2 one-electron operator,<br>using a wave function of the outermost electron (i.e. <nlm|r^2|nlm>, where n,l,m - quantum numbers of the outermost electron).<br> Molpro provides me with the second moment (SM) operator (<a href="http://www.molpro.net/info/2012.1/doc/manual/node68.html" target="_blank" data-mce-href="http://www.molpro.net/info/2012.1/doc/manual/node68.html">http://www.molpro.net/info/2012.1/doc/manual/node68.html</a>).<br>But it contains summation over all electrons in a system (i.e. SM_{XX} = \sum_{i=1}^{N} x_{i}^{2}, where x_{i} is the x coordinate of the i^{th} electron,<br>N - total number of electrons in the system).<br> Will this sum reduce to 1 electron (i.e. SM_{XX}= x_{1}^{2}), when I ask molpro to calculate the expectation value of the<br>SM operator using wave function of the outermost electron? <br><br>I'm interested in it, because I want to calculate the Le Roy radius (<a href="http://leroy.uwaterloo.ca/leroy_radius.html" target="_blank" data-mce-href="http://leroy.uwaterloo.ca/leroy_radius.html">http://leroy.uwaterloo.ca/leroy_radius.html</a>).<br><br>Alexander Medvedev,<br>student of the 5th course,<br>Chemistry department,<br>Chair of laser chemistry,<br>MSU</BODY></HTML>