Thank you Bert for your fast reply.
I have been working on your modified geometry but I end up again in a c2h optimized structure that is highly deformed and gives negative excitations (possible conical intersection?).
autosym is not able to detect the c2h symmetry on your modified geometry, therefore if I optimize it with c1 symmetry I get this minimum (which is very similar to the one I obtain with different codes with and without symmetry):
Ti 0.00000312 1.29508791 -0.41023362
Ti -0.00000292 -1.29508723 0.41023465
O 0.00002610 -2.57710993 -0.59171972
O -0.00002665 2.57710896 0.59172361
O -1.25308248 0.00005145 0.00001102
O 1.25308283 -0.00005117 -0.00001593
when I optimize your modified geometry with c2h symmetry I get this distorted structure:
Ti -0.26744804 1.30749556 0.00000000
Ti 0.26744804 -1.30749556 0.00000000
O 1.44788061 -2.71073052 0.00000000
O -1.44788061 2.71073052 0.00000000
O 0.00000000 0.00000000 -1.26048208
O 0.00000000 0.00000000 1.26048208
I tried to reoptimize the c2h one with no symmetry and I end up in a structure very close to the first one with no symmetry.
I cannot understand what could be the source of this problem.
Thanks,
Enrico
Quote:Bert Oct 29th 10:40 amHi Enrico,
There is indeed an issue with finding the symmetry for this system due to the way NWChem tries to find the symmetry.
In the mean time, the following geometry block will do what you want it to do:
GEOMETRY
symmetry group c2h
Ti 0.0000000 1.3590396 0.0000000
Ti 0.0000000 -1.3590396 0.0000000
O 1.3409217 -2.2797801 0.0000000
O -1.3409217 2.2797801 0.0000000
O 0.0000000 0.0000000 -1.2512390
O 0.0000000 0.0000000 1.2512390
END
Bert
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