Dear Atefe,

Suppose you are going to perform a SP calculation over PtCl2 at BLYP D3 def2-TZVP level and the "lanl2dz" basis set should be employed for Pt. The Orca input file should simply be as follows:

! BLYP D3 def2-TZVP def2/J noautostart miniprint nopop

%maxcore 6000

%pal nprocs 8 end

* xyz 0 1

Cl -3.34513754 -1.30969607 0.00000000

Cl 1.43486246 -1.30969607 0.00000000

Pt -0.95513754 -1.30969607 0.00000000 newGTO "lanl2dz" end

*

Regards,

Saeed

Saeedreza Emamian hi tnx a million times for your answer

I want to do some MD simulations. could u please write me about where I shod put this command? because orca command said I should write this command(NewECP Pt "lanl2dz-SD" end # Different ECP for Pd) but you dont write it

%basis

"6-31g(d)" # All elements

NewECP Pt "lanl2dz-SD" end # Different ECP for Pd

! MD PBE 6-31G(D) LANL2DZ-ecp/Pd

%md

timestep 1.0_fs

initvel 300_K

cell cube 15.0

thermostat berendsen 300_K timecon 5.0_fs

dump position stride 1 filename "trajectory.xyz"

run 2000

end

Why do not you use def2 series instead of lanl2dz? Def2-TZVP covers almost all elements and is much more efficient and accurate than lan. Note, however, that def2 bases automatically apply pseudo potential for heavy elements such as Pt and an explicit definition of ECP is not needed.

Unfortunately, I have no experience in MD simulation!

Saeedreza Emamian it takes too much time and I think changing the basis set is the best way to reduce it

As can be seen from "Table 6.5: Overview of library keywords for ECPs and associated basis sets available in ORCA" in ORCA manual, the ECP name suitable for Lanl2DZ pseudopotential basis set should be HayWadt or LANL2. In consequence, the Orca input file should be as follows:

! BLYP D3 opt noautostart miniprint nopop

%maxcore 6000

%pal nprocs 8 end

%basis

NewGTO Pt "lanl2dz" end

NewECP Pt "lanl2" end

NewGTO Cl "6-31G(d)" end

end

* xyz 0 1

Pt -1.69319837 -0.86107090 0.00000000

Cl -3.97319837 -0.86104281 0.00000000

Cl -0.93318522 0.21372151 1.86161255

Cl -0.93322446 -3.01068474 0.00000000

Cl -0.93318522 0.21372151 -1.86161255

*

Can anybody suggest a suitable basis set for optimization of Cu(I) complex