[Wien] ATPAR Error in lapw1 for NMR calculation of 1H

[Michael Fechtelkord]

Hello Peter,


I checked the 1H NMR on a simple Brucite sample with just 3 atoms (Al O 
H). Lapw1 now runs fine and the addition of the additional local orbital 
for H in case.in1c works: No NaNs now. So Shifts can be calculated for 
1H now.


Thanks and wishing a nice weekend!


Michael


Am 04.12.2025 um 20:06 schrieb Peter Blaha:
> Hi,
> I can confirm the problem.
>
> It comes from the fact that the higher H-LOs have energies above 
> 1000Ry and case.in1 has lines like:
> ...
>  0.30   27  0     (GLOBAL E-PARAMETER WITH n OTHER CHOICES, global 
> APW/LAPW)
>  0   0.30000   0.0000 CONT 1
>  0 100.02000    0.000 CONT 1
>  0 235.14000    0.000 CONT 1
>  0 424.38000    0.000 CONT 1
>  0 666.78000    0.000 CONT 1
>  0 961.24000    0.000 CONT 1
>  01306.58000    0.000 CONT 1
>
> In subroutine  find_nloat.F  the l-value is read by read(5,*) and 
> without a blank between the l and the energy it reads a wrong l-value.
> Thus it determines   nloat_max as 7, which is too low later on.
>
> It does not happen, when you co-select another element (Oxygen), 
> because then it determines nloat_max correctly from an O atom, where 
> the energies are smaller.
>
> Solution:
> Modify in    find_nloat.F  the line
>
>         read(5,*) l
> by
>         read(5,'(i2)') l
>
> Regards
> Peter Blaha
>
> Am 26.11.2025 um 18:57 schrieb Michael Fechtelkord via Wien:
>> Hello all,
>>
>>
>> I am trying to calculate the 1H chemical shift tensor of Bassanite 
>> CaSO4 * 0.5 H2O.
>>
>> I have added a second line in case.in1c for all Hs
>>
>> 0.30    2  0      (GLOBAL E-PARAMETER WITH n OTHER CHOICES, global 
>> APW/ LAPW)
>>   0    0.30     0.0000 CONT 1
>>   1    0.30     0.0000 CONT 1
>>
>> and for initializing the case.inc1_nmr file I focused on H only 
>> (x_nmr_lapw -mode in1 -focus H)
>>
>>
>> Running then x_nmr_lapw -p gives lapw1 ATR errors for eigenvector 
>> calculations:
>>
>>   'ATPAR' - NLOAT too small (NLOAT =  7, L =  0 JATOM = 22)
>>   'ATPAR' - NLOAT too small (NLOAT =  7, L =  0 JATOM = 22)
>>   'ATPAR' - NLOAT too small (NLOAT =  7, L =  0 JATOM = 22)
>>   'ATPAR' - NLOAT too small (NLOAT =  7, L =  0 JATOM = 22)
>>
>> It does not happen when I focus on 2 atoms e.g. O and H (complete NMR 
>> local orbitals for O and H).
>>
>>
>> Any ideas here would help.
>>
>>
>> Best regards and thanks in advance
>>
>> Michael
>>
>>
>
-- 
Dr. Michael Fechtelkord

Institut für Geowissenschaften
Ruhr-Universität Bochum
Universitätsstr. 150
D-44780 Bochum

Phone: +49 (234) 32-24380
Fax:  +49 (234) 32-04380
Email: Michael.Fechtelkord at ruhr-uni-bochum.de
Web Page: https://www.ruhr-uni-bochum.de/kristallographie/kc/mitarbeiter/fechtelkord/