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[Enrico <enrico.avenati@yahoo.com>]

Hi,

i'm trying to do some calculation on LaNi5H7, but i can't make it! 
 The crystallographic data is the following

space group number  :   186
setting             :   1
Hermann-Mauguin     :   P 6_3 m c
Laue group          :   6/mmm
point group         :   6mm

positions     

12 d   x,y,z                 -y,x-y,z              -x+y,-x,z           
       -x,-y,z+1/2           y,-x+y,z+1/2          x-y,x,z+1/2         
       -y,-x,z               -x+y,y,z              x,x-y,z             
       y,x,z+1/2             x-y,-y,z+1/2          -x,-x+y,z+1/2       

6 c    x,-x,z                x,2x,z                -2x,-x,z            
       -x,x,z+1/2            -x,-2x,z+1/2          2x,x,z+1/2          

2 b    1/3,2/3,z             2/3,1/3,z+1/2         

2 a    0,0,z                 0,0,z+1/2             

I've tried to input the data of the assymetric unit as in VASP ( usually it
doens't work in ABINIT)

No   name       crystal coordinates          
                  x        y        z           
  -------------------------------------------
  1     La     0,0000   0,0000   0,9990  
  2     NI     0,3333   0,6667   0,0110    
  3     ni     0,3333   0,6667   0,4881    
  4     ni     0,5000   0,5000   0,2500    
  5     h      0,3333   0,6667   0,8203   
  6     h      0,1593   0,8407   0,2952   
  7     h      0,5069   0,4931   0,0577     

It didn't worked in fact.

 I tried to input the unit formula La2Ni10H14, it didn't work again cause i'm
told it takes translation into account.
Amy inputs have been tried many times with spcgrp specified and other
specification.

In the end i tought to input LaNi5H7 with all the XRED that are not originated
by translation (+ 1/2) as shown from crystallographic data.

The calculation start but the spcgrp is wrong , and if i specify it the
calculation stop cause the symmetric images can't be found!
 
Here follows my input, I hope you can help.

Thank you very much.

#UNIT CELL LaNi5H7

acell  5.409 5.409 8.600 Angstr

rprim
1 0 0 
-0.5 sqrt(0.75) 0
0 0 1

spgroup 186

ntypat 3 # 3 types of atoms

znucl  57 28 1

natom  13 # atom per cell

typat  1 5*2 7*3# LaNi5H7
 
xred
0            0            0.999  # La 2a
1/3          2/3          0.0011 #Ni 2b
1/3          2/3          0.4881 #Ni 2b
0.4999      -0.4999        1/4 #Ni 6c
0.4999       0.9888        1/4 #
-0.9888     -0.4999       1/4 #
1/3          2/3          0.8203 # H 2b
0.1593      -0.1593       0.2952 # H 6c
0.1593       0.3186       0.2952 #
-0.3186     -0.1593       0.2952#
0.5069      -0.5069       0.0577 # H 6c
0.5069       0.0038       0.0577#
-0.0038     -0.5069       0.0577#



#RECIPROCAL SPACE INTEGRETION
kptopt 1
ngkpt 2 2 2

nshiftk 1
shiftk 0.0 0.0 0.5 
 
nband 72
tsmear 0.02
occopt 4

#PLANE WAVES
ecut 100

#SCF PROCEDURE
nstep 200
ixc 1
toldfe 1.0d-7