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Re^3: Getting wrong result for TiO2 HOMO-LUMO gap...

Siddheshwar Chopra
sidhusai@gmail.com


Dear Alex,
A BIG Thanks for that explanation. The problem is solved..
But could you try with 6-31G also. I got the same problem here too. Please have a look at that.

Kind Regards,

On Tue May 27 '14 3:28pm, Alex Granovsky wrote
----------------------------------------------
>The relevant lines of output are:

> TOTAL NUMBER OF SHELLS              =   11
> TOTAL NUMBER OF BASIS FUNCTIONS     =   50
> NUMBER OF ELECTRONS                 =   38
> CHARGE OF MOLECULE                  =    0
> STATE MULTIPLICITY                  =    1
>
> NUMBER OF OCCUPIED ORBITALS (ALPHA) =   19
> NUMBER OF OCCUPIED ORBITALS (BETA ) =   19
>

> TOTAL NUMBER OF ATOMS               =    3
> THE NUCLEAR REPULSION ENERGY IS      124.9770929777

>and

>
> THE ECP RUN REMOVES   14 CORE ELECTRONS, AND THE SAME NUMBER OF PROTONS.
>

> THE ADJUSTED NUCLEAR REPULSION ENERGY=       53.0405413922

>So to get the HOMO # you should take 19 and then subtract 14/2  

>Kind regards,
>Alex Granovsky
>
>
>
>
>On Tue May 27 '14 12:34pm, Alex Granovsky wrote
>-----------------------------------------------
>>Hi,

>>You should take into account that ECP removes core electrons.
>>As a result, HOMO becomes orbital number 12, while LUMO is orbital
>>number 13. The HOMO-LUMO gap is then ca. 3 eV.

>>Kind regards,
>>Alex Granovsky
>>
>>
>>
>>
>>On Tue May 27 '14 10:16am, Siddheshwar Chopra wrote
>>---------------------------------------------------
>>>Dear Users,
>>>Please see the following code I am using to run for a single TiO2 molecule. I have used SBKJC and also 6-31G to get almost similar results for HOMO-LUMO gap. I am getting around 0.7 eV. However as far as literature goes, I should have got ~ 3 eV. As it a sngle TiO2 molecule, gap should have opened.

>>> $SYSTEM MEMORY=34459319 aoints=dist TIMLIM=5295600 KDIAG=-1 $END
>>> $CONTRL INTTYP=HONDO ICUT=11 ITOL=30 RUNTYP=OPTIMIZE SCFTYP=RHF $END
>>> $CONTRL DFTTYP=B3LYP COORD=UNIQUE NZVAR=3 $END
>>> $CONTRL MAXIT=10000 MOLPLT=.t. PLTORB=.t. ECP=SBKJC $END
>>> $BASIS GBASIS=SBKJC $END
>>> $STATPT opttol=10E-7 NSTEP=200 Method=GDIIS HSSEND=.TRUE. $END
>>> $SCF dirscf=.t. fdiff= .f. diis=.t. $END  
>>> $DFT HFX(1)=0.15 LMAX=41 NRAD=99 $end
>>> $ZMAT DLC=.t. AUTO=.t. $END
>>> $SCF NCONV=7 $END
>>> $DATA
>>>TiO2
>>>C1
>>> TI         22.0  -2.7439906036  -2.7281069598  -0.4118294433
>>> O           8.0  -3.1097257096  -4.1115914499   0.4209344416
>>> O           8.0  -3.1706230814  -1.3977023214   0.4765961088
>>> $END

>>>Please refer the following reference for the same:

>>> J. Mater. Chem. A,2014, 2,637

>>>Please help,

>>>Kind Regards,


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