chktyp warning in AkaiKKR

Posted on : July 16, 2026 (Thu) 19:49:15

by Umbu Kapading Hadambiwa

Hello,
I am performing a calculation with AkaiKKR for a base-centered orthorhombic (brvtyp=bso) structure. The calculation runs, but I always obtain the following warnings:
***wrn in chktyp...check atomic position or atom type.
atoms 1 and 2 are assigned to the same type, but it obviously is wrong

***wrn in chktyp...check atomic position or atom type.
atoms 1 and 3 are assigned to the same type, but it obviously is wrong

***wrn in chktyp...check atomic position or atom type.
atoms 2 and 4 are assigned to the same type, but it obviously is wrong
My input file is:
go data/Co2CrIr_Cmcm

bso 9.74693 0.78876 1.72590 90.0 90.0 90.0

0.001 1.2 sra pbe mag init

update 6 300 0.005

3

Co 1 0.0 0.0 3
27 1.0
Cr 1 0.0 0.0 3
24 1.0
Ir 1 0.0 0.0 3
77 1.0

8

0.33753001 0.18006996 0.25000000 Co
0.81993004 0.66246999 0.25000000 Co
0.18006996 0.33753001 0.75000000 Co
0.66246999 0.81993004 0.75000000 Co

0.33775751 0.66224249 0.25000000 Cr
0.66224249 0.33775751 0.75000000 Cr

0.83371959 0.16628041 0.25000000 Ir
0.16628041 0.83371959 0.75000000 Ir
According to the manual, atomic positions can be specified using fractional coordinates with respect to the primitive vectors, so I believe the input format is correct.
Could anyone explain what exactly triggers the chktyp warning? Does it indicate that my atomic positions are inconsistent with the selected Bravais lattice (bso), or is it related to symmetry detection? Is there anything obviously wrong with the way I defined the four Co atoms?
Any advice would be greatly appreciated.