# SCF convergence detoriates and oscillates after certain steps during structure relaxation with vacancies

**URL:** <https://discourse.abinit.org/t/scf-convergence-detoriates-and-oscillates-after-certain-steps-during-structure-relaxation-with-vacancies/3101>\
**Category:** Ground state\
**Created:** [March 31, 2022, 12:01pm UTC](https://discourse.abinit.org/t/scf-convergence-detoriates-and-oscillates-after-certain-steps-during-structure-relaxation-with-vacancies/3101 "2022-03-31T12:01:48Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![rajaraman](https://discourse.abinit.org/user_avatar/discourse.abinit.org/rajaraman/32/132_2.png) [@rajaraman](https://discourse.abinit.org/u/rajaraman)\
**Post date:** [March 31, 2022, 12:01pm UTC](https://discourse.abinit.org/t/scf-convergence-detoriates-and-oscillates-after-certain-steps-during-structure-relaxation-with-vacancies/3101/1 "2022-03-31T12:01:48Z")

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Hai,  
I am doing positron lifetime calculation in Au 3x3x3 supercell with 4 vacancies

SCF convergence suddenly deteriorates and starts oscillating

TC-DFT STEP 1 - ELECTRONIC GROUND-STATE CALCULATION  
ETOT 1 -14370.949818419 -1.437E+04 3.327E-04 1.252E+02 2.056E-02 2.056E-02  
ETOT 2 -14369.885027813 1.065E+00 2.879E-05 4.583E-01 3.268E-03 1.729E-02  
ETOT 3 -14369.788157398 9.687E-02 3.758E-05 7.578E-01 1.903E-03 1.919E-02  
ETOT 4 -14369.780950526 7.207E-03 2.757E-05 7.040E-03 3.757E-04 1.919E-02  
ETOT 5 -14369.782041279 -1.091E-03 8.689E-06 2.215E-03 2.671E-04 1.945E-02  
ETOT 6 -14369.782148266 -1.070E-04 9.593E-06 5.818E-04 4.515E-05 1.948E-02  
ETOT 7 -14369.782142363 5.903E-06 8.083E-06 5.763E-05 4.448E-05 1.952E-02  
**ETOT 8 -14369.782144917 -2.554E-06 2.338E-06 1.829E-05 1.343E-05 1.951E-02**  
**ETOT 9 -14378.181294990 -8.399E+00 1.224E+01 2.552E-01 1.413E-02 1.930E-02**  
ETOT 10 -14369.724128201 8.457E+00 6.569E-03 2.497E-03 1.406E-02 1.950E-02  
ETOT 11 -14369.773722613 -4.959E-02 1.882E-03 2.826E-04 7.493E-05 1.950E-02

looking at the log following warning occurs when a sudden jump occurs

!COMMENT  
src\_file: m\_lobpcg2.F90  
src\_line: 665  
message: |  
**An old style abi\_xorthonormalize happened but now I’ll try to continue 😉**  
…

[au333\_4\_corner\_vac\_sft3\_middle\_lt\_relax.abi](https://discourse.abinit.org/uploads/short-url/vHZ0ek2248epRRWH0LBb8tEXIdP.abi) (9.4 KB)  
[au333\_4\_corner\_vac\_sft3\_middle\_lt\_relax.abo](https://discourse.abinit.org/uploads/short-url/bKAIYfUstVkZCf8h1BthyXxezJe.abo) (118.3 KB)  
[log.txt](https://discourse.abinit.org/uploads/short-url/fX2RlOpUZEOZzDAvKZBCEwFWHzb.txt) (257.6 KB)

ps: I am using custom potential generated with 5s5p5d6s (added txt extension to upload)  
this potential is verified to reproduce lattice parameter and bulk modulus

[Au.LDA-PW-paw\_5s5p5d6s.abinit.txt](https://discourse.abinit.org/uploads/short-url/b27IEadzOXGQft7u7lLOr5EzRYa.txt) (694.5 KB)

Looking forward to suggestions for this convergence issue  
Thanks  
-rajaraman

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**Author:** ![bguster](https://discourse.abinit.org/letter_avatar_proxy/v4/letter/b/ac8455/32.png) [@bguster](https://discourse.abinit.org/u/bguster)\
**Post date:** [April 5, 2022, 9:21pm UTC](https://discourse.abinit.org/t/scf-convergence-detoriates-and-oscillates-after-certain-steps-during-structure-relaxation-with-vacancies/3101/2 "2022-04-05T21:21:48Z")

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Hello Rajaraman,

Your approach looks perfectly fine, but I would just increase the number of bands. I tried a quick test with 100 more bands and it worked fine.  
Good luck!  
Bogdan

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<div class="post-metadata">

**Author:** ![rajaraman](https://discourse.abinit.org/user_avatar/discourse.abinit.org/rajaraman/32/132_2.png) [@rajaraman](https://discourse.abinit.org/u/rajaraman)\
**Post date:** [April 6, 2022, 5:21am UTC](https://discourse.abinit.org/t/scf-convergence-detoriates-and-oscillates-after-certain-steps-during-structure-relaxation-with-vacancies/3101/3 "2022-04-06T05:21:01Z")

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Thank you Bogdan.

I never thought of increasing nband (tried removing manual definition and allowed code to calculate optimum nband, which I used as a guideline)

I just started tinkering nline and nnsclo.

I will try your suggestion.

Is it the reason for the  
" **An old style abi\_xorthonormalize happened but now I’ll try to continue**" warning when it start oscillating?

Thanks a lot  
-rajaraman