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Re^6: Getting wrong result for TiO2 HOMO-LUMO gap...

Alex Granovsky
gran@classic.chem.msu.su


Most likely, you are using wrong conversion factor from au to eV.

Kind regards,
Alex Granovsky



On Thu May 29 '14 7:11am, Siddheshwar Chopra wrote
--------------------------------------------------
>Dear Alex,
>Yes you said right..HOMO orbital is 19th. But I am getting 0.68eV using 6-31G. Could you please help me?

>Kind Regards,

>On Wed May 28 '14 3:49pm, Alex Granovsky wrote
>----------------------------------------------
>>Hello,

>>with 6-31G, HOMO is orbital # 19

>>Kind regards,
>>Alex Granovsky
>>
>>
>>On Wed May 28 '14 8:24am, Siddheshwar Chopra wrote
>>--------------------------------------------------
>>>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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