[molpro-user] Extrapolation to the complete basis set limit of def2-anzvp basis sets.
sasha medvedev
vinsanity305 at mail.ru
Thu Oct 24 21:24:23 BST 2013
Hello, professor Kirk Peterson.
1) It's great that you have clarified the situation with extrapolation properties of def2- basis sets.
Unfortunately, they were not designed for it.
2) And your remark about 3-point extrapolation, involving DZ basis set, is important.
3) The last:
>also, you might want to take a look at the top of the file def2-nzvpp-orb.libmol in your molpro lib directory for some notes about def2- vs. dhf-
I have checked file def2-nzvpp-orb.libmol:
lib/def2-nzvpp-orb.libmol $Revision: 2010.1 $
*
* Basis sets taken from Turbomole basis set library at
* http://bases.turbo-forum.com/TURBOMOLE_BASISSET_LIBRARY/tbl.html
* on 2009-11-18.
*
* Notes:
* - In Turbomole, some of the def2- basis sets are associated with slightly
* modified versions of Stuttgart-Bonn-Koeln pseudopotentials to account for
* non-existing support of higher ECP projectors in Turbomole. In here,
* these sets are associated with the original versions of these
* ECPs, not the modified def2- ones. This is not likely to cause
* noticable changes in energy differences.
*
* - As with the def2-ECPs, elements 37-48 and 55-80 are associated with
* ECPxxMWB ECPs (xx=28 for Rb-Cd, xx=46 for Cs-La, xx=60 for Hf-Hg) while
* elements 49-54 and 81-86 are associated with ECPxxMDF ECPs.
* The MDF basis sets are newer and supposedly more accurate. Note that
* the newer MDF sets in the respective sizes also exist for elements
* 37-48 and 55-80, but for consistency with Turbomole, the MWB versions
* were chosen also here.
*
* - Gerald Knizia, 2009-11-20
--------------------------------------------------------
I can't get your idea about comparison of def2- and dhf- basis set (which should be presented in this file, as far as I understand).
May be I have an old version of def2-nzvpp-orb.libmol file?
May be you mean those basis sets, which go with MDF ECPs? (def2-nzvp/pp-2c)
Sasha Medvedev.
Wednesday, 23 october 2013, 15:25 UTC from "Peterson, Kirk" <kipeters at wsu.edu>:
>Dear Alexander (Sasha),
>
>the def2- basis sets to my knowledge were never designed explicitly for basis set extrapolation. They do provide a series of basis sets that range from small to large, but I am not aware of a study that uses them in CBS extrapolations. You might though
want to consider the TZVPP and QZVPP sets since these have f and g functions, respectively, compared to TZVP and QZVP. In any event if you are using lmax-style extrapolations, you only need 2 basis sets to do this. Typically 3-point extrapolations that include
a DZ-quality set is not recommended except for specialized extrapolation formulas.
>
>best,
>
>-Kirk
>
>PS - also, you might want to take a look at the top of the file def2-nzvpp-orb.libmol in your molpro lib directory for some notes about def2- vs. dhf-
>
>
>On Oct 23, 2013, at 5:17 AM, sasha medvedev < vinsanity305 at mail.ru > wrote:
>>Dear molpro users.
>>We calculate ab initio potentials of alkali metal - inert gase weakly bound molecules.
>>Our research group uses def2-asvp,atzvp,aqzvp basis sets for extrapolation to a complete basis set limit (2 and 3 point formulae from molpro manual-Lx,LHx,Ex2) .
>>But we stress, that these basis sets are not suitable for a 3-point extrapolation at all, because the lmax is the same for asvp and atzvp basis sets for Rb and Cs atoms:
>>For Cs :
>>def2-asvp
>>Library entry Cs ECP ECP46MDF selected for group 1
>> Library entry CS S def2-SVP selected for orbital group 1
>> Even tempered Cs S diffuse selected for group 1 nprim= 1 centre= 0.005 ratio= 2.271 dratio= 1.000
>> Library entry CS P def2-SVP selected for orbital group 1
>> Even tempered Cs P diffuse selected for group 1 nprim= 1 centre= 0.003 ratio= 5.198 dratio= 1.000
>> Library entry CS D def2-SVP selected for orbital group 1
>> Even tempered Cs D diffuse selected for group 1 nprim= 1 centre= 0.008 ratio= 4.004 dratio= 1.000
>>
>>def2-atzvp
>>Library entry Cs ECP ECP46MDF selected for group 1
>> Library entry CS S def2-TZVP selected for orbital group 1
>> Even tempered Cs S diffuse selected for group 1 nprim= 1 centre= 0.005 ratio= 2.271 dratio= 1.000
>> Library entry CS P def2-TZVP selected for orbital group 1
>> Even tempered Cs P diffuse selected for group 1 nprim= 1 centre= 0.003 ratio= 5.198 dratio= 1.000
>> Library entry CS D def2-TZVP selected for orbital group 1
>> Even tempered Cs D diffuse selected for group 1 nprim= 1 centre= 0.004 ratio= 3.904 dratio= 1.000
>>
>>For Rb:
>>def2-asvp
>> Library entry Rb ECP ECP28MDF selected for group 2
>> Library entry RB S def2-SVP selected for orbital group 2
>> Even tempered Rb S diffuse selected for group 2 nprim= 1 centre= 0.006 ratio= 2.320 dratio= 1.000
>> Library entry RB P def2-SVP selected for orbital group 2
>> Even tempered Rb P diffuse selected for group 2 nprim= 1 centre= 0.003 ratio= 6.503 dratio= 1.000
>> Library entry RB D def2-SVP selected for orbital group 2
>> Even tempered Rb D diffuse selected for group 2 nprim= 1 centre= 0.003 ratio= 8.238 dratio= 1.000
>>
>>def2-atzvp
>> Library entry Rb ECP ECP28MDF selected for group 1
>> Library entry RB S def2-TZVP selected for orbital group 1
>> Even tempered Rb S diffuse selected for group 1 nprim= 1 centre= 0.006 ratio= 2.287 dratio= 1.000
>> Library entry RB P def2-TZVP selected for orbital group 1
>> Even tempered Rb P diffuse selected for group 1 nprim= 1 centre= 0.006 ratio= 2.500 dratio= 1.000
>> Library entry RB D def2-TZVP selected for orbital group 1
>> Even tempered Rb D diffuse selected for group 1 nprim= 1 centre= 0.003 ratio= 3.569 dratio= 1.000
>>
>>So, a 3-point extrapolation is forbidden here, because we need at least 3 basis sets with different lmax (unfortunately, we have only two: atzvp,aqzvp).
>>--------------------------------------------------------------------------------------------------------------------------------------
>>Besides that, extrapolation formulae depend on the cardinal number n (which is the part of the basis set name - i.e. 2 for asvp, 3 for atzvp, 4 for aqzvp, and should be equal to the lmax ). When we looked through output file, we noticed, that the same basis set has different lmax for different atoms:
>>
>>For Cs (def2-aqzvp basis set with ecp46mdf)
>>
>> Library entry Cs ECP ECP46MDF selected for group 2
>> Library entry AR S def2-QZVP selected for orbital group 1
>> Even tempered Ar S diffuse selected for group 1 nprim= 1 centre= 0.068 ratio= 2.441 dratio= 1.000
>> Library entry AR P def2-QZVP selected for orbital group 1
>> Even tempered Ar P diffuse selected for group 1 nprim= 1 centre= 0.044 ratio= 2.497 dratio= 1.000
>> Library entry AR D def2-QZVP selected for orbital group 1
>> Even tempered Ar D diffuse selected for group 1 nprim= 1 centre= 0.123 ratio= 2.407 dratio= 1.000
>> Library entry AR F def2-QZVP selected for orbital group 1
>> Even tempered Ar F diffuse selected for group 1 nprim= 1 centre= 0.223 ratio= 2.440 dratio= 1.000
>> Library entry AR G def2-QZVP selected for orbital group 1
>> Even tempered Ar G diffuse selected for group 1 nprim= 1 centre= 0.403 ratio= 2.500 dratio= 1.000
>>
>> Library entry CS S def2-QZVP selected for orbital group 2
>> Even tempered Cs S diffuse selected for group 2 nprim= 1 centre= 0.008 ratio= 1.465 dratio= 1.000
>> Library entry CS P def2-QZVP selected for orbital group 2
>> Even tempered Cs P diffuse selected for group 2 nprim= 1 centre= 0.004 ratio= 2.468 dratio= 1.000
>> Library entry CS D def2-QZVP selected for orbital group 2
>> Even tempered Cs D diffuse selected for group 2 nprim= 1 centre= 0.004 ratio= 2.911 dratio= 1.000
>> Library entry CS F def2-QZVP selected for orbital group 2
>> Even tempered Cs F diffuse selected for group 2 nprim= 1 centre= 0.235 ratio= 2.500 dratio= 1.000
>>
>>For Rb (def2-qzvp with ecp28mdf)
>>
>> Library entry Rb ECP ECP28MDF selected for group 2
>> Library entry AR S def2-QZVP selected for orbital group 1
>> Even tempered Ar S diffuse selected for group 1 nprim= 1 centre= 0.068 ratio= 2.441 dratio= 1.000
>> Library entry AR P def2-QZVP selected for orbital group 1
>> Even tempered Ar P diffuse selected for group 1 nprim= 1 centre= 0.044 ratio= 2.497 dratio= 1.000
>> Library entry AR D def2-QZVP selected for orbital group 1
>> Even tempered Ar D diffuse selected for group 1 nprim= 1 centre= 0.123 ratio= 2.407 dratio= 1.000
>> Library entry AR F def2-QZVP selected for orbital group 1
>> Even tempered Ar F diffuse selected for group 1 nprim= 1 centre= 0.223 ratio= 2.440 dratio= 1.000
>> Library entry AR G def2-QZVP selected for orbital group 1
>> Even tempered Ar G diffuse selected for group 1 nprim= 1 centre= 0.403 ratio= 2.500 dratio= 1.000
>>
>> Library entry RB S def2-QZVP selected for orbital group 2
>> Even tempered Rb S diffuse selected for group 2 nprim= 1 centre= 0.006 ratio= 2.064 dratio= 1.000
>> Library entry RB P def2-QZVP selected for orbital group 2
>> Even tempered Rb P diffuse selected for group 2 nprim= 1 centre= 0.005 ratio= 2.591 dratio= 1.000
>> Library entry RB D def2-QZVP selected for orbital group 2
>> Even tempered Rb D diffuse selected for group 2 nprim= 1 centre= 0.003 ratio= 2.877 dratio= 1.000
>> Library entry RB F def2-QZVP selected for orbital group 2
>> Even tempered Rb F diffuse selected for group 2 nprim= 1 centre= 0.341 ratio= 2.500 dratio= 1.000
>>
>>So, def2-aqzvp basis set can change its cardinal number n, but it is still called aqzvp!
>>Does it mean, that we should use different n (i.e. cardinal numbers or lmax of a particular basis set) in the extrapolation formulae for the same basis set, if lmax changes?
>>
>>So, it is impossible to extrapolate the energy of the system, which contains atoms with different lmax (when we use def2-anzvp
>>basis sets), because in such a case n is not determined (something like (n1+n2)/2 - which is not even an integer). Am I right?
>>
>>I am also interested in scientific papers, in which extrapolation to the complete basis set limit of def2-asvp/atzvp/aqzvp basis sets is carried out (if extrapolation is allowed for def2-anzvp basis sets).
>>
>>Alexander Medvedev,
>>student of the 5th course of
>>Lomonosov Moscow State University
>>Department of Chemistry
>>Chair of Laser Chemistry
>>_______________________________________________
>>Molpro-user mailing list
>>Molpro-user at molpro.net
>>http://www.molpro.net/mailman/listinfo/molpro-user
>
--
s m
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