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<DIV><FONT size=2>
<DIV><FONT size=3 face="Times New Roman">Dear users,</FONT></DIV>
<DIV><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV><FONT size=3 face="Times New Roman">In my work, I try to get the normal
mode coordinates of a molecule by molpro, but when i compare the
result get from molpro with from Gaussian98 code, I find the different
results ! </FONT></DIV>
<DIV>
<DIV><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV><FONT size=3 face="Times New Roman">For example: O--C--S
(linear molecule), V3 antisymmetry normal mode (Q3) :</FONT></DIV>
<DIV><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV><FONT size=3 face="Times New Roman">in Gaussian: Q3: -0.50 Oz +
0.86 Cz - 0.07 Sz ( molecule located at Z
axis)</FONT></DIV>
<DIV><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV><FONT size=3 face="Times New Roman">in molpro: Q3:
-0.14098 Oz + 0.2364 Cz -0.01822 Sz</FONT></DIV>
<DIV><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV>
<DIV><FONT size=4><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><FONT size=3>To switch from Molpro normal coordinate
coefficient to gaussian one</FONT></SPAN><FONT face="Times New Roman"><FONT
size=3>,</FONT> <FONT size=3> two molpro-users told me two
different methods as</FONT>:</FONT></FONT></DIV>
<DIV><FONT face="Times New Roman"></FONT> </DIV>
<DIV><FONT face="Times New Roman">(1) </FONT><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><FONT size=3> calculate the reduced mass (mured) corresponding to the
normal coordinate of interest.<BR></FONT><FONT color=#000000><FONT size=3><SPAN
style="COLOR: red"><FONT color=#000000>mured= 1/sqrt( sum over all cartesian
displacements of the square of the molpro coefficient divided by the
corresponding atomic mass )<BR> Here <FONT color=#0000ff>mured =1/sqrt [
(0.14098)^2/15.99 + (0.2364)^2/12 + (0.01822)^2/31.97]=
13.006</FONT><BR> multiplying the molpro coeff. by 1 / sqrt(mured)</FONT>
</SPAN>gives the corresponding gaussian normal coordinate
coefficient</FONT></FONT></SPAN></DIV>
<DIV><FONT face="Times New Roman"></FONT> </DIV>
<DIV><FONT size=3 face="Times New Roman">This method gives: </FONT></DIV>
<DIV><SPAN lang=EN-US><FONT size=3><FONT face="Times New Roman"><SPAN
style="mso-spacerun: yes"> <SPAN
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT
face="Times New Roman">reduced mass:</FONT> </SPAN></SPAN>13.008
</FONT></FONT></SPAN></DIV>
<DIV>
<P style="TEXT-INDENT: 5.25pt; MARGIN: 0cm 0cm 0pt; mso-char-indent-count: .5"
class=MsoNormal><SPAN lang=EN-US><FONT face="Times New Roman"><SPAN
style="mso-spacerun: yes"> <FONT size=3>Q3: </FONT></SPAN><FONT
size=3>-5.084378723760641E-001 Oz</FONT><SPAN style="mso-spacerun: yes"><FONT
size=3> + 8.526378218576923E-001
Cz - 6.570958769342700E-002</FONT><SPAN
style="mso-spacerun: yes"><FONT
size=3> Sz</FONT> </SPAN> </SPAN></FONT></SPAN></P>
<P style="TEXT-INDENT: 5.25pt; MARGIN: 0cm 0cm 0pt; mso-char-indent-count: .5"
class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"><FONT
face="Times New Roman"></FONT></SPAN></SPAN> </P><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><SPAN style="mso-spacerun: yes"><FONT
size=3> (2) <SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><FONT size=3>The reduced mass can be calculated from
1/(sum-of-squares of molpro normal coordinate coefficient ):</FONT>
</SPAN></FONT></SPAN></SPAN></DIV>
<DIV><SPAN style="COLOR: red"><FONT face="Times New Roman"><FONT
color=#000000> </FONT><FONT color=#0000ff> mured=
1/( 0.14098^2 + 0.2364^2 + 0.01822^2 )= <SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><FONT size=3>13.14030</FONT></SPAN></FONT></FONT></SPAN></DIV>
<DIV><SPAN style="COLOR: red"><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><FONT color=#000000 size=3>multiplying the molpro coeff. by 1 /
sqrt(mured) gives the corresponding gaussian normal coordinate
coefficient</FONT></SPAN></SPAN></DIV>
<DIV><SPAN style="COLOR: red"><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><FONT color=#000000
face="Times New Roman"></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN style="COLOR: red"><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><FONT color=#000000 size=3>This method gives: </FONT></DIV>
<DIV>
<DIV><SPAN lang=EN-US><FONT color=#000000><FONT size=3><SPAN
style="mso-spacerun: yes"> <SPAN
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT
face="Times New Roman">reduced mass: 13.1403</FONT></SPAN></SPAN>
</FONT></FONT></SPAN></DIV>
<DIV>
<P style="TEXT-INDENT: 5.25pt; MARGIN: 0cm 0cm 0pt; mso-char-indent-count: .5"
class=MsoNormal><SPAN lang=EN-US><FONT color=#000000><FONT size=3><SPAN
style="mso-spacerun: yes">Q3: <SPAN
lang=EN-US>-5.110462461425969E-001<SPAN
style="mso-spacerun: yes"> </SPAN></SPAN></SPAN>Oz<SPAN
style="mso-spacerun: yes">
+ 8.570120005877189E-001<SPAN
style="mso-spacerun: yes"> </SPAN> Cz -
6.604668918421140E-002<SPAN style="mso-spacerun: yes"> </SPAN><SPAN
style="mso-spacerun: yes"> Sz </SPAN> </SPAN></FONT></FONT></SPAN></P></DIV></SPAN></SPAN></DIV>
<DIV><SPAN style="COLOR: red"><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><SPAN style="mso-spacerun: yes"><FONT
face="Times New Roman"></FONT></SPAN></SPAN></SPAN></SPAN> </DIV>
<DIV><SPAN style="COLOR: red"><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><SPAN style="mso-spacerun: yes"><FONT size=3><FONT color=#000000>The
difference between these two method seems to origin from the
different cognizance that <SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US>the use or not of mass-weighted coordinates for Molpro normal
coordinate coefficient . What is the true case in Molpro? (</SPAN>Which
method is right ?) Looking forward to your suggestions!</FONT>
</FONT>
<DIV><FONT color=#000000></FONT> </DIV>
<DIV><FONT color=#000000 size=3>Thanks in
advance!</FONT></DIV></SPAN></SPAN></SPAN></SPAN></DIV>
<DIV><SPAN style="COLOR: red"><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><SPAN
style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA"
lang=EN-US><SPAN style="mso-spacerun: yes"><FONT size=3><FONT
color=#000000> </FONT> </FONT>
<DIV><FONT color=#000000 size=3>Eryin Feng</FONT></DIV>
<DIV><FONT color=#000000 size=3></FONT> </DIV>
<DIV><FONT color=#000000 size=3>department of physics,</FONT></DIV>
<DIV><FONT color=#000000 size=3>Anhui normal
university,China</FONT></DIV></SPAN></SPAN></SPAN></SPAN></DIV></DIV></DIV>
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