exercises:2014_ethz_mmm:basis_sets
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Basis Sets
In this exericse you will compare different basis sets and use them for computing the binding energy of an H2 molecule.
The cp2k basis set format is the following:
Nsets n1 lmin lmax Nexp Ncontr exp1 contr1 contr2 contr3 ... exp2 contr4 contr5 contr6 ... Nexp.... n2 lmin lmax Nexp Ncontr exp1 contr1 contr2 contr3 ... exp2 contr4 contr5 contr6 ... Nexp.... ...
Nsets = number of sets.
n1,n2… = main quantum number (but it gets ignored by the program!)
lmin = min l (angular quantum number) of the set ( s = 0 ; p = 1 ; d = 2 …)
lmax = max l (angular quantum number) of the set ( s = 0 ; p = 1 ; d = 2 …)
Nexp = number of exponents of the set
Ncontr = number of contaction coefficients per angular quantum number
As an example:
2 2 Sets 1 0 0 1 1 Set 1: lmin=0 ; lmax=0 (→ s functions!) ; 1 exponent ; 1 contraction 0.35 1 exponent1 of set 1 ; contraction 1 1 1 1 1 Set 2: lmin=1 ; lmax=1 (→ p functions!) ; 1 exponenet ; 1 contraction 0.6 1 exponent1 of set 2 ; contraction
Part I: Create your own basis set for H
1.Step
Save the following input file. Comment lines are marked with !
- mybasis.inp
&GLOBAL PROJECT H-mybasis RUN_TYPE ENERGY &END GLOBAL &FORCE_EVAL METHOD Quickstep ! Electronic structure method (DFT,...) &DFT LSD ! Requests a spin-polarized calculation for an odd number of electrons MULTIPLICITY 2 ! Multiplicity = 2S+1 (S= total spin momentum) &POISSON ! Solver requested for non periodic calculations PERIODIC NONE PSOLVER MT ! Type of solver &END POISSON &QS ! Parameters needed to set up the Quickstep framework METHOD GAPW ! Method: gaussian and augmented plane waves &END QS &XC ! Parametes needed to compute the electronic exchange potential &XC_FUNCTIONAL NONE ! No xc_functional &END XC_FUNCTIONAL &HF ! Hartree Fock exchange. In this case is 100% (no fraction specified). &SCREENING ! Screening of the electronic repulstion up to the given threshold. This section is needed EPS_SCHWARZ 1.0E-10 ! Threshold specification &END SCREENING &END HF &END XC &END DFT &SUBSYS &CELL ABC 10.0 10.0 10.0 PERIODIC NONE ! Non periodic calculations. That's why the POISSON scetion is needed &END CELL &COORD H 0.0 0.0 0.0 &END COORD &KIND H &BASIS ! Basis set 2 1 0 0 1 1 0.35 1 1 0 0 1 1 0.6 1 &END POTENTIAL ALL ! Potential for all electron calculations &END KIND &END SUBSYS &END FORCE_EVAL
exercises/2014_ethz_mmm/basis_sets.1395759382.txt.gz · Last modified: 2020/08/21 10:14 (external edit)