Metadynamics with NWChem


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Just Got Here
12:55:43 PM PST - Mon, Jan 13th 2020
Wrong geometry conversion when running metadynamics for periodic system
Hi Nwchem users and developers

I am having issues with running metadynamics calculation due wrong geometry conversion for angstrom to a.u. Below are the input and output geometry after conversion.

      1. input geometry

geometry units angstrom nocenter noautosym noautoz print xyz
O 1.8721262729142700 2.6772977892108072 3.0457634041233832
H 1.8721262729142700 3.4405367892108294 2.4494544041234025 mass 2.0
H 1.8721262729142700 1.9140587892107965 2.4494544041234025 mass 2.0
O 3.0007245151628497 1.6057278693301698 1.2975208145820827
H 3.0007245151628497 2.3689668693301926 0.7012118145821018 mass 2.0
H 3.0007245151628497 0.8424888693301587 0.7012118145821018 mass 2.0
end

  1. set nwpw:cif_filename neptunium4

nwpw
 np_dimensions -1 4

 xc xperdew91

 simulation_cell units angstroms

  boundary_conditions periodic

  lattice

   lat_a 3.91

   lat_b 3.91

   lat_c 3.91

  end

    1. Output geometry after conversion to AU

atomic composition:
    O   :  2     H   :  4



initial position of ions:

       1 O    (    3.53781   -2.32947   -1.63317 ) - atomic mass=  15.995

       2 H    (    3.53781   -0.88716   -2.76003 ) - atomic mass=   2.000

       3 H    (    3.53781    3.61705   -2.76003 ) - atomic mass=   2.000

       4 O    (   -1.71828    3.03439    2.45196 ) - atomic mass=  15.995

       5 H    (   -1.71828   -2.91213    1.32510 ) - atomic mass=   2.000

       6 H    (   -1.71828    1.59207    1.32510 ) - atomic mass=   2.000


    1. The right geometry output after conversion

O 3.53781 5.05936 5.755659
H 3.53781 6.50167 4.628799
H 3.53781 3.61705 4.628799
O 5.67055 3.03439 2.451960
H 5.67055 4.47669 1.325100
H 5.67055 1.59207 1.325100


The wrong geometry conversion causes error in the metadynamics calculations because the metadynamics calculation is done with a wrong geometry. Please I need help with fixing the error.