Hi everyone,
I am a new GULP learner and a basic question bothers me when I try to fit the potential parameter using a CIF file of AlF3 as below. Warning like “the system is not neutral” would appear and the program is terminated. I see that the CIF file only give the irreducible atoms and the species I use seems to be neutral in the chemical formula (partial charge: Al:+1.8; F:-0.6). So I don’t know the reason and hope to get some help. The CIF file (searched in the Findit Software), input and output files are listed below.
CIF file:
data_29131-ICSD #?2010 by Fachinformationszentrum Karlsruhe, and the U.S. Secretary of #Commerce on behalf of the United States. All rights reserved. _database_code_ICSD 29131 _audit_creation_date 1986/08/04 _audit_update_record 2010/08/01 _chemical_name_systematic 'Aluminium Trifluoride' _chemical_formula_structural 'Al F3' _chemical_formula_sum 'Al1 F3' _publ_section_title ; Structure of the trifluorides of aluminium, iron, cobalt, rhodium, and palladium ; loop_ _citation_id _citation_journal_abbrev _citation_year _citation_journal_volume _citation_page_first _citation_page_last _citation_journal_id_ASTM primary 'Nature (London)' 1931 128 303 303 NATUAS _publ_author_name 'Ketelaar, J.A.A.' _cell_length_a 4.93 _cell_length_b 4.93 _cell_length_c 6.25 _cell_angle_alpha 90. _cell_angle_beta 90. _cell_angle_gamma 120. _cell_volume 131.55 _cell_formula_units_Z 3 _symmetry_space_group_name_H-M 'P 3 2 1' _symmetry_Int_Tables_number 150 loop_ _symmetry_equiv_pos_site_id _symmetry_equiv_pos_as_xyz 1 'x-y, -y, -z' 2 '-x, -x+y, -z' 3 'y, x, -z' 4 '-x+y, -x, z' 5 '-y, x-y, z' 6 'x, y, z' loop_ _atom_type_symbol _atom_type_oxidation_number Al3+ 3 F1- -1 loop_ _atom_site_label _atom_site_type_symbol _atom_site_symmetry_multiplicity _atom_site_Wyckoff_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy _atom_site_attached_hydrogens Al1 Al3+ 1 a 0 0 0 1. 0 Al2 Al3+ 2 d 0.3333 0.6667 0.667 1. 0 F1 F1- 3 f 0.667 0.667 0.5 1. 0 F2 F1- 6 g 0.167 0.833 0.167 1. 0 #End of data_29131-ICSD
Input file:
fit opti prop conp cell 4.93 4.93 6.25 90 90 120 frac Al 0 0 0 Al 0.3333 0.6667 0.667 F 0.667 0.667 0.5 F 0.167 0.833 0.167 space 150 species Al 1.8 F -0.6 buckingham Al Al 0 1 0 0.0 10.0 0 0 0 Al F 47181.82 5.48 22.75 0.0 10.0 1 0 0 F F 11510.594 0.225005 29.257 0.0 12.0 0 0 0
Output files:
Job Started at 01:28.49 23rd May 2021 Number of CPUs = 1 Total number of configurations input = 1 Configuration number = 1 **** Unit cell is not charge neutral ** **** Sum of charges = 7.2000000000 ** **** Check that a special position atom ** **** coordinate has not been varied ** -------------------------------------------------------------------------------- No. Atomic x y z Charge Occupancy Number (frac) (frac) (frac) (e) -------------------------------------------------------------------------------- 1 Al c 0.000000 0.000000 0.000000 1.800000 1.0000 2 Al c 0.333300 0.666700 0.667000 1.800000 1.0000 3 Al c 0.333300 0.666600 0.667000 1.800000 1.0000 4 Al c 0.333400 0.666700 0.667000 1.800000 1.0000 5 Al c 0.666600 0.333300 0.333000 1.800000 1.0000 6 Al c 0.666700 0.333400 0.333000 1.800000 1.0000 7 Al c 0.666700 0.333300 0.333000 1.800000 1.0000 8 F c 0.667000 0.667000 0.500000 -0.600000 1.0000 9 F c 0.333000 0.000000 0.500000 -0.600000 1.0000 10 F c 0.000000 0.333000 0.500000 -0.600000 1.0000 11 F c 0.167000 0.833000 0.167000 -0.600000 1.0000 12 F c 0.167000 0.334000 0.167000 -0.600000 1.0000 13 F c 0.666000 0.833000 0.167000 -0.600000 1.0000 14 F c 0.334000 0.167000 0.833000 -0.600000 1.0000 15 F c 0.833000 0.666000 0.833000 -0.600000 1.0000 16 F c 0.833000 0.167000 0.833000 -0.600000 1.0000 --------------------------------------------------------------------------------
Sorry to bother and all guidance would be greatly appreciated!
Sincerely,
Ji Yao