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Re^3: E(MP4) - E(MP3) = -26 hartrees?

Alex Granovsky
gran@classic.chem.msu.su


Dear David,

Sorry, currently there is no way to get the required information from Firefly's output.
It is assumed that there is some fatal mistake with user's input like duplicate atoms etc...


Kind regards,
Alex Granovsky




On Sat Apr 9 '16 8:37am, David Shobe wrote
------------------------------------------
>Related question:

>When you get the following error message
>THE INPUT BASIS SET CONTAINS A LINEAR DEPENDENCE
>it doesn't tell you which functions are redundant, unlike the case for a near linear dependence.  How do you know which functions to delete?

>Thanks for you help so far,
>--David
>
>
>On Wed Apr 6 '16 10:07pm, Alex Granovsky wrote
>----------------------------------------------
>>Dear David,
>>Dear Pedro,

>>Search this site on "mp4(d)" returns these two useful threads:
>>
>>
>>http://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C393fb1c3f2vS-7378-1007-00.htmhttp://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C393fb1c3f2vS-7378-1007-00.htmhttp://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C393fb1c3f2vS-7378-1007-00.htmhttp://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C393fb1c3f2vS-7378-1007-00.htm

>>http://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C3d2d5e75bcsK-8577-846+00.htmhttp://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C3d2d5e75bcsK-8577-846+00.htmhttp://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C3d2d5e75bcsK-8577-846+00.htmhttp://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C3d2d5e75bcsK-8577-846+00.htm
>>
>>
>>In brief, this job has almost linearly dependent basis set. As printed
>>in the output file:
>>
>>
>>

 THE OVERLAP MATRIX HAS    4 EIGENVALUES BELOW 1.1E-04
 THE SMALLEST OF THESE IS 1.35832E-09. 

>>The eigenvalue of overlap matrix of 1.35832E-09 corresponds
>>to a severe quasi-linear dependence.

>>The sensitivity of MP4(D) term of the MP4 energy to the linear
>>dependence in the AO basis set has been already discussed on this
>>forum several times. The MP4(D) term is the most sensitive one
>>because during its computation one needs to transform integrals and
>>other quantities from AO to MO basis, then back from MO to AO,
>>and finally from AO to MO again. Each transformation kills up to
>>several significant digits of the result (more precisely,
>>the number of digits lost is directly related to the condition
>>number of the overlap matrix) if all orbitals (including virtual
>>ones) are not computed very precisely. So in the worst case like
>>this one, one can lost all significant digits.
>>
>>
>>What to do?

>>One need to delete some orbitals to increase the smallest
>>eigenvalue of the overlap matrix.

>>As output indicates, the most problematic orbital is:

>>

   0.2857E-08   -    C   5  S,   SHELL  31,   AO   73

>>i.e. the S part of the diffuse L shell on the atom C5

>>I attached archive with modified input file as well as
>>the corresponding output file. In the new input, the
>>problematic orbital was removed by replacing L shell
>>located on atom C5 by P shell. Otherwise, the $DATA
>>group of the modified input is equivalent to the initial
>>$DATA and $BASIS groups.

>>I also increased ICUT and ITOL, and disabled fdiff.
>>Finally, I tightened nconv to 6 as recommended in
>>output.

>>The smallest eigenvalue of overlap matrix is now:

>>

 THE SMALLEST OF THESE IS 4.10644E-08.

>>i.e. ca. 30 times better!
>>
>>
>>As a result, we obtain:

>>

 RESULTS OF MOLLER-PLESSET 4TH ORDER CORRECTION ARE

            E(RHF)       =      -191.5685568750

            E(D,2)       =        -0.6457464825
            E(MP2)       =      -192.2143033575

            E(D,3)       =        -0.0166674371
            E(D,2+3)     =        -0.6624139197
            E(MP3)       =      -192.2309707947

            E(S,4)       =        -0.0073886039
            E(D,4)       =        -0.0200238070
            E(D,2+3+4)   =        -0.6824377267
            E(T,4)       =        -0.0337953970
            E(R+Q,4)     =         0.0168396781
            E(SDTQ,4)    =        -0.0443681298
            E(SDTQ,2+3+4)=        -0.7067820495
            E(MP4-SDTQ)  =      -192.2753389245

>>Hope this helps.

>>Kind regards,
>>Alex Granovsky
>>
>>
>>
>>
>>
>>
>>
>>
>>On Mon Apr 4 '16 0:12am, David Shobe wrote
>>------------------------------------------
>>>Is this the correct MP4 energy for this molecule (1,3-pentadiyne)?

>>> RESULTS OF MOLLER-PLESSET 4TH ORDER CORRECTION ARE

>>>            E(RHF)       =      -191.5694925024

>>>            E(D,2)       =        -0.6494633272
>>>            E(MP2)       =      -192.2189558295

>>>            E(D,3)       =         0.2696414733
>>>            E(D,2+3)     =        -0.3798218539
>>>            E(MP3)       =      -191.9493143563

>>>            E(S,4)       =        -0.0517477560
>>>            E(D,4)       =       -26.2790188653
>>>            E(D,2+3+4)   =       -26.6588407192
>>>            E(T,4)       =        -0.0344433158
>>>            E(R+Q,4)     =         0.0171693598
>>>            E(SDTQ,4)    =       -26.3480405772
>>>            E(SDTQ,2+3+4)=       -26.7278624311
>>>            E(MP4-SDTQ)  =      -218.2973549335
>>>


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