Models and strategies for metallic systems: bulk and surfaces Klaus Doll University of Ulm Institute of Electrochemistry Albert-Einstein-Allee 47 D-89069 Ulm, Germany ISAMS, Regensburg, July 2015 Motivation: • explanation of experimental results (experiments performed e.g. at a synchrotron) • importance of topics such as catalysis, corrosion • technical: test of local basis set for metallic systems Outline: • computational parameters • structure optimisation with gradients • bulk metals • surfaces • adsorption 1. Computational Parameters • Method: usually density functional theory; functionals: PWGGA, PBE: most popular LDA: overbinds RHF, B3LYP: underbind see e.g. M. Sgroi, C. Pisani, M. Busso, Thin solid films 400, 64(2001) in general: Fock exchange gives vanishing density of states at Fermi energy see Ashcroft & Mermin, Solid State Physics, chapter 17 • basis set: diffuse functions are necessary: enlarge basis, reoptimize exponents • ~k-points: typically (16×16×16) for bulk; (16×16) for surface studies • finite temperature scheme used: keyword SMEAR, typical value 0.01 Eh or lower; very low values for magnetic materials required; e.g. Ni: Curie temperature is 631 K = ˆ 0.0020 Eh 1 E(T = 0) = 2 (E(T ) + F (T )) (E0 in output) makes numerical integration more stable Convergence • PROBLEM, especially for metals • general rule: start from a simple problem • if you have never done a calculation with CRYSTAL: start with an insulator, e.g. NaCl, reproduce data from literature • metals: 1. step: bulk 2. step: thin surface 3. step: thick surface 4. step: adsorbate + surface • convergence tools: - always use FMIXING, often very large mixing required (> 90%) - usually no level shifting - speedup possible with keywords ANDERSON, BROYDEN (avoid level shift together with these keywords!) • verify solution!!! check: Mulliken population, binding energy, surface energy ..., compare schemes: try FMIXING only (safest, but slow), try FMIXING+ANDERSON ... 2. Structure optimisation with gradients Gradients with respect to nuclear positions: K. Doll, V. R. Saunders and N. M. Harrison, Int. J. Quant. Chem. 82, 1 (2001) K. Doll, Comp. Phys. Comm. 137, 74 (2001) Gradient with respect to the cell parameter: 3 D periodic systems: K. Doll, R. Dovesi, R. Orlando, Theo. Chem. Acc. 112, 394 (2004) 1 D, 2D periodic systems: K. Doll, R. Dovesi, R. Orlando, Theor. Chem. Acc. 115, 354 (2006) Input for a full optimisation minimum input: OPTGEOM ENDOPT default: full geometry optimisation (atom positions, unit cell) for 3 D periodic systems, the stress tensor is printed in output file e.g. input.out (first geometry) and SCFOUT.LOG (following geometries) σlm 3 ∂E X 1 ∂E = aim = V ∂lm i=1 ∂ail in the case of hydrostatic pressure, with a pressure p: σ= −p 0 0 0 −p 0 0 0 −p ⇒ pressure p available as an analytical derivative, and also the enthalpy H = E + pV K. Doll, Mol. Phys. 108, 223-227 (2010) optimisation with external hydrostatic pressure: keyword EXTPRESS alternatively CVOLOPT to constrain the volume (1) Gradient for metals Question: is there an extra term for metals, due to the shape of the Fermi surface, compared to the case of insulators ? Answer: • at zero temperature, there is no extra term • at finite temperature (keyword SMEAR), the gradient is consistent with the free energy M. Weinert and J. W. Davenport, Phys. Rev. B 45, 13709 (1992) R. M. Wentzcovitch, J. L. Martins, and P. B. Allen, Phys. Rev. B 45, 11372 (1992) Test: compare numerical and analytical gradients Example 1: Cu bulk, LDA (at a = 3.4 Å) smearing − ∂E ∂a temperature (Eh ) (numerical, 0.001 0.0315 0.01 0.0310 0.03 0.0212 0.05 0.0098 − ∂F ∂a Eh ) (numerical, a0 0.0315 0.0319 0.0390 0.0540 − ∂F ∂a Eh ) (analytical, a0 0.0317 0.0320 0.0393 0.0542 Example 2: Cl/Cu(111) smearing temperature: 0.001 Eh K. Doll, Chem. Phys. Lett. 535, 187 (2012) Eh a0 ) 2. Bulk metals Basis set reoptimization is recommended: • start from an existing basis set e.g. Cu: M. D. Towler, R. Dovesi and V.R. Saunders Phys. Rev. B 52, 10150 (1995) • reoptimize diffuse exponents (e.g. exponents with value smaller than 1) keep inner exponents fixed • reoptimization means: determination of exponent with lowest energy of reference system (here: copper bulk) Reoptimization: How does it work? e.g. copper outermost exponents were: sp : 0.559 and d : 0.430 good for Cu2+, e.g. KCuF3 1) 2) 3) 4) add one sp reoptimize reoptimize reoptimize shell, start with e.g. sp 0.6, 0.2 and d : 0.430 (guess) tight sp, keep others fixed diffuse sp, keep others fixed d, keep others fixed is energy converged? - if not return to step 2 typically: 2-3 iterations of this type necessary Result: sp 0.596, 0.150 d 0.392 (PWGGA level) metals: outermost diffuse sp exponent usually in the range 0.1 ... 0.2 Copper bulk: input file Copper Metal CRYSTAL 000 225 3.63 1 29 0. 0. 0. END 29 8 0 0 8 2.0 1.0 398000.0 56670.0 12010.0 3139.0 947.2 327.68 128.39 53.63 0 1 6 8.0 1.0 1022.0 ← space group ← lattice constant ← copper ← basis set ..... 0.000227 0.001929 0.01114 0.05013 0.17031 0.3693 0.4030 0.1437 -0.00487 0.00850 238.9 -0.0674 0.06063 80.00 -0.1242 0.2118 31.86 0.2466 0.3907 13.33 0.672 0.3964 4.442 0.289 0.261 0 1 4 8.0 1.0 54.7 0.0119 -0.0288 23.26 -0.146 -0.0741 9.92 -0.750 0.182 4.013 1.031 1.280 0 1 1 1.0 1.0 1.582 1.0 1.0 0 1 1 0.0 1.0 0.596 1.0 1.0 0 1 1 0.0 1.0 0.150 1.0 1.0 0 3 4 10.0 1.0 48.54 0.031 13.55 0.162 4.52 0.378 1.47 0.459 0 3 1 0.0 1.0 0.392 1.0 99 0 END ← reoptimized exponent ← reoptimized/new exponent ← reoptimized exponent ← ..... end of basis set input DFT EXCHANGE PWGGA CORRELAT PWGGA END SHRINK 16 32 MAXCYCLE 60 FMIXING 70 NOSHIFT SMEAR 0.01 PPAN END ← PW-functional ← ~k-point sampling ← enable more SCF cycles ← convergence tool ← no level shifting (0.6 hartree level shift default in CRYSTAL14) ← finite temperature scheme ← Mulliken population use keyword FIXINDEX when comparing calculations at various lattice constants (smooth potential curve) Band structure calculation (properties-part) BAND Copper band structure 5 8 500 10 15 1 0 0 0 0 4 0 4 G-X 4 0 4 4 2 6 X-W 4 2 6 4 4 4 W-L 4 4 4 0 0 0 L-G 0 0 0 4 8 4 G-K-X’ END visualise with: xmgrace -nxy BAND.DAT 5: 8: 500: 10 15: 1 0: 5 lines in Brillouin zone ˆ ( 48 0 48 ) divisor, e.g. X is ( 12 0 21 ) but is expressed as (4 0 4 ) = number of points computed along path first, last band to be plotted: Cu, 1s, 2s, 2p, 3s, 3p: 9 bands, flat, core-like Cu 4s, 3d : 6 bands, the interesting ones output options note the different paths G-X and G-K-X’ ; X = ( 84 0 84 ) and X’=( 48 lattice vector: ( 48 88 48 ) = (0 1 0) + ( 48 0 48 ) 8 4 8 8) differ by a reciprocal Brillouin zones: see e.g. : C. J. Bradley and A. P. Cracknell, The Mathematical Theory of Symmetry in Solids (Clarendon Press, Oxford, 1972) W. Setyawan, S. Curtarolo, Comp. Mat. Sci. 49, 299 (2010) incorrect Brillouin zone is a frequent source of error! Cohesive properties: a [Å] Ecoh[Eh] B[GPa] HF 3.95 0.018 69 LDA 3.53 0.182 195 PWGGA 3.63 0.143 155 exp. 3.604 0.129 142 K. Doll, N. M. Harrison, Chem. Phys. Lett. 317, 282 (2000) 3. Surfaces model: finite number of layers not repeated in the third dimension ⇒ no vacuum layers difference in geometry input: SLABCUT 111 13 ← cut slab ← (111) surface ← 3 layers use e.g. keyword ANDERSON to achieve convergence nice exercise: try as many layers as possible Compute surface energy: Two ways of calculating surface energies: [1] Esurf ace = [2] Esurf ace = 1 2 (Eslab (n) − nEbulk ) 1 2 Eslab (n) − [Eslab (n) Cu(111): computed 2.01 J/m2 (PW); exp.: 1.83 J/m2 − Eslab(n − n m)] m 4. Adsorption on metallic surfaces Cl/Cu(111): Coverage: one third of a monolayer exp.: structure is √ 3× √ 3 R30◦ (LEED): P. J. Goddard and R. M. Lambert, Surf. Science 67, 180 (1977) fcc hollow as adsorption site (SEXAFS): M. D. Crapper, C. E. Riley, P. J. J. Sweeney, C. F. McConville, and D. P. Woodruff, Europhys. Lett. 2, 857 (1986) Input Chlorine on copper CRYSTAL 000 225 ← space group 3.63 ← lattice constant 1 29 0. 0. 0. ← copper SLAB ← 3 layers, (111) surface 111 13 SUPERCEL ← supercell 21 12 ATOMINSE ← add chlorine adsorbate, hcp site 1 17 0.0 0.0 3.99 ATOMDISP 3 1 0.0 0.0 -0.04 ← relaxation of top Cu layer 2 0.0 0.0 -0.04 ← relaxation of top Cu layer 3 0.0 0.0 -0.04 ← relaxation of top Cu layer END 17 6 0 0 8 2. 1. 135320. 19440. 4130. 1074. 323.4 111.1 43.4 18.18 0 1 6 8. 1. 324.8 73.00 23.71 9.138 3.930 1.329 0 1 3 7. 1. 4.755 1.756 0.785 0 1 1 0. 1. 0.294 0 1 1 0. 1. 0.090 0 3 1 0. 1. 0.50 0.000225 0.00191 0.01110 0.04989 0.1703 0.3683 0.4036 0.1459 ← Cl basis set: on the web, modified: enlarged (d-exponent) slightly different diffuse exponents -0.00763 0.00820 -0.0829 0.0605 -0.1046 0.2115 0.2540 0.3765 0.695 0.3967 0.399 0.186 -0.3740 -0.4754 1.3400 -0.0340 0.1617 0.9250 1. 1. 1. 1. 1. 29 8 0 0 8 2.0 1.0 398000.0 0.000227 56670.0 0.001929 12010.0 0.01114 3139.0 0.05013 947.2 0.17031 327.68 0.3693 128.39 0.4030 53.63 0.1437 0 1 6 8.0 1.0 1022.0 -0.00487 0.00850 238.9 -0.0674 0.06063 80.00 -0.1242 0.2118 31.86 0.2466 0.3907 13.33 0.672 0.3964 4.442 0.289 0.261 0 1 4 8.0 1.0 54.7 0.0119 -0.0288 23.26 -0.146 -0.0741 9.92 -0.750 0.182 4.013 1.031 1.280 0 1 1 1.0 1.0 1.582 1.0 1.0 0 1 1 0.0 1.0 0.596 1.0 1.0 0 1 1 0.0 1.0 0.150 1.0 1.0 0 3 4 10.0 1.0 48.54 0.031 13.55 0.162 4.52 0.378 1.47 0.459 0 3 1 0.0 1.0 0.392 1.0 99 0 END ← Cu basis set, on the web .... DFT EXCHANGE PWGGA CORRELAT PWGGA END SHRINK 16 32 SCFDIR MAXCYCLE 100 FMIXING 90 ANDERSON NOSHIFT SMEAR 0.01 PPAN END ← PW91 functional ← convergence tools Results of the optimization: Site dCl−Cu Eadsorption Cl coordination number fcc 2.40 Å 3.696 eV hcp 2.41 Å 3.691 eV bridge 2.33 Å 3.609 eV top 2.17 Å 3.235 eV exp.: fcc 2.39 ± 0.02 Å ∼ 2.6 eV (SEXAFS) (therm. desorption) Rules: • higher coordination number ⇒ higher binding energy • lower coordination number ⇒ shorter bond length (only one “bond“ which is strong) K. Doll, N. M. Harrison, Chem. Phys. Lett. 317, 282 (2000). 3 3 2 1 Cl/Ag(111) Site dCl−Ag Eadsorption fcc 2.62 Å hcp 2.62 Å bridge 2.54 Å top 2.38 Å exp.a,b: fcc 2.48 Å; 2.70 Å 3.039 3.027 2.959 2.573 ∼ 2.4 eV eV eV eV eV CRYSTAL: K. Doll, N. M. Harrison, Phys. Rev. B 63, 165410 (2001) a A. G. Shard and V. R. Dhanak, J. Phys. Chem. B 104, 2743 (2000) b G. M. Lamble, R. S. Brooks, S. Ferrer, D. A. King and D. Norman, Phys. Rev. B 34, 2975 (1986) CRYSTAL results confirmed by VASP-calculation: fcc hcp bridge top 2.64 2.64 2.56 2.39 Å Å Å Å 3.124 3.117 3.044 2.684 eV eV eV eV VASP: L. Jia, Y. Wang, and K. Fan, J. Phys. Chem. B 107, 3813 (2003) Compute effective chlorine radius: subtract radius of metal : rM e √ = a/ 8 substrate Cu Ag Ni a rCl 3.63 Å 1.12 Å 4.10 Å 1.17 Å 3.53 Å 1.09 Å compare with data from Kittel’s book: radius of Cl: 0.99 Å radius of Cl−: 1.81 Å consistent with Mulliken charge: Cl carries always only small negative charge (∼ -0.1 ... -0.2 |e|) Charge of chlorine consider: Cl on Ag(111) site fcc hcp bridge top charge 3s level, relative to EF -0.198 -0.563 -0.204 -0.562 -0.218 -0.555 -0.252 -0.532 note: Mulliken charge increases ⇒ 3s level gets destabilized (nuclear charge less well screened because more electronic charge on chlorine) Potassium as adsorbate Cu(111)(2×2)-K: top site occupied! S. Å. Lindgren, L. Walldén, J. Rundgren, P. Westrin and J. Neve, Phys. Rev. B 28, 6707 (1983). Simulations prove: Cu atom under potassium adsorbate is pushed into substrate atoms 1,2,3 upwards, relative to clean surface Substate rumpling crucial: Site dK−Cu nn Eadsorption per Cl atom with rumpling (without rumpling) fcc 3.11 Å 1.265 eV (1.249) hcp 3.11 Å 1.263 eV (1.243) bridge 3.04 Å 1.265 eV (1.243) top 2.83 Å 1.287 eV (1.227) exp.a: top (SEXAFS) 3.05 ± 0.02 Å a D. L. Adler, I. R. Collins, X. Liang, S. J. Murray, G. S. Leatherman, K.-D. Tsuei, E. E. Chaban, S. Chandravarkar, R. McGrath, R. D. Diehl and P. H. Citrin, Phys. Rev. B 48, 17445 (1993) energy gain by substrate rumpling: ∼ 0.02 eV for fcc, hcp, bridge, but 0.06 eV for top site! K. Doll, Eur. Phys. J. B 22, 389 (2001). K/Ag(111): two coverages considered: coverage Mulliken charge on K bond length [Å] exp.a [Å] h i h binding energy K Eatom K 3s, 3p levels (relative to EF ) 3s 3p (2 × 2) 0.25 √ √ ( 3 × 3)R30◦ 0.3333 0.24 3.20 3.27 ± 0.03 0.041 0.16 3.27 3.29± 0.02 0.042 -1.194 -0.600 -1.184 -0.590 a K-K distance recuced ⇒ stronger repulsion ⇒ depolarisation ⇒ larger radius and bond length ⇒ core levels destabilized G. S. Leatherman, R. D. Diehl, P. Kaukasoina and M. Lindroos, Phys. Rev. B 53, 10254 (1996) K. Doll, Phys. Rev. B 66, 155421 (2002) CO/Pt(111) Photograph: Wikimedia Commons Standard functionals give wrong site: fcc (PW91) versus top (experiment) ”The CO/Pt(111) puzzle” P.J. Feibelman, B. Hammer, J. K. Nørskov, F. Wagner, M. Scheffler, R. Watwe, R. Dumesic, J. Phys. Chem. 105, 4018 (2001) Possible solution when adsorbed: 1) C gives charge to Pt 2) Pt back donates charge: more in the case of the hollow site, less in the case of the top site Standard functionals favor charge transfer too strong (gaps too small), prefer hollow site Suggestions: • B3LYP, Cluster+extrapolation A. Gil, A. Clotet, J. M. Ricart, G. Kresse, M. Garcı́a-Hernández, N. Rösch, and Ph. Sautet, Surf. Sci. 530, 71 (2003) • LDA+U: G. Kresse, A. Gil, and Ph. Sautet, Phys. Rev. B 68, 073401 (2003) Periodic B3LYP calculation Standard-functional (PW91) B3LYP 3 fold hollow site bridge site +0.06 eV +0.02 eV top site +0.08 eV -0.04 eV CO charge: ∼ -0.05 ∼ -0.35 B3LYP: describes band gaps and excitation energies better CO/Pt(111): K. Doll, Surf. Sci. 573, 464 (2004) CO/Cu(111): M. Neef and K. Doll, Surf. Sci. 600, 1085 (2006) Work function Work function: electrostatic potential at infinity, minus Fermi energy But: Cu(111), input as early in the talk: Φ = 0.142 Eh exp.: 0.183 Eh strongly basis set dependent, e.g. when varying the outermost diffuse exponent! other properties are much less basis set dependent! solution: use basis functions in the vacuum (keyword GHOSTS) 1-2 ghost layers are sufficient: without ghosts: 1 ghost layer on each side: 2 ghost layers on each side: experiment: 0.142 0.189 0.190 0.183 Eh Eh Eh Eh K. Doll, Surf. Sci. 600, L321 (2006) see also: P. J. Feibelman, Phys. Rev. B 51, 17867 (1995) 5. Summary • geometry and energetics are in very good agreement with experiment and plane-wave results • typical properties: total energy, geometry, Mulliken population (surprisingly reliable!), core levels, charge+spin density maps, overlayer density of states • basis sets must be carefully chosen, possibly readjusted work function: use ghosts in the vacuum region above the surface • B3LYP versus standard functional shows: HOMO and LUMO position important for CO adsorption • Gaussian type orbitals suitable for all types of structures, also metals, all-electron calculations are possible review: K. Doll, Ab initio calculations with a Gaussian basis set for metallic surfaces and the adsorption thereon, in ”Quantum Chemical Calculations of Surfaces and Interfaces of Materials”, edited by Vladimir Basiuk and Piero Ugliengo, American Scientific Publishers, 2009, p. 41-53 Basis sets In the following, some of the basis sets used are given. Note that they are calibrated for systems where the atom is neutral. For systems where the atom is positively charged, it may be necessary to remove the outermost diffuse exponents, or shift them to higher values, possibly reoptimise. Lithium 33 0 0 6 2. 1. 840.0 0.00264 217.5 0.00850 72.3 0.0335 19.66 0.1824 5.044 0.6379 1.5 1.0 0 1 1 1. 1. 0.50 1.0 1.0 0 1 1 0. 1. 0.10 1.0 1.0 K. Doll, N. M. Harrison, V. R. Saunders, J. Phys.: Condens. Matter 11, 5007-5019 (1999) note: calibrated for Li metal - for a system where Li is positively charged, it may be necessary to remove the outermost diffuse exponent, or shift it to a higher value, possibly reoptimise. Copper 29 8 0 0 8 2.0 1.0 398000.0 56670.0 12010.0 3139.0 947.2 327.68 128.39 53.63 0 1 6 8.0 1.0 1022.0 238.9 80.00 31.86 13.33 4.442 0 1 4 8.0 1.0 54.7 23.26 9.92 4.013 0 1 1 1.0 1.0 1.582 0 1 1 0.0 1.0 0.596 0 1 1 0.0 1.0 0.150 0 3 4 10.0 1.0 48.54 13.55 4.52 1.47 0 3 1 0.0 1.0 0.392 0.000227 0.001929 0.01114 0.05013 0.17031 0.3693 0.4030 0.1437 -0.00487 -0.0674 -0.1242 0.2466 0.672 0.289 0.00850 0.06063 0.2118 0.3907 0.3964 0.261 0.0119 -0.146 -0.750 1.031 -0.0288 -0.0741 0.182 1.280 1.0 1.0 1.0 1.0 1.0 1.0 0.031 0.162 0.378 0.459 1.0 K. Doll, N. M. Harrison, Chem. Phys. Lett. 317, 282 (2000) note: calibrated for Cu metal - for a system where Cu is positively charged, it may be necessary to remove the outermost diffuse sp exponent, or shift it to a higher value, possibly reoptimise. Nickel 28 8 0 0 8 2.0 1.0 367916.0 52493.9 11175.8 2925.4 882.875 305.538 119.551 49.9247 0 1 6 8.0 1.0 924.525 223.044 74.4211 29.6211 12.4721 4.2461 0 1 4 8.0 1.0 56.6581 21.2063 8.4914 3.6152 0 1 1 2.0 1.0 1.5145 0 1 1 0.0 1.0 0.63 0 1 1 0.0 1.0 0.13 0 3 4 8.0 1.0 41.0800 11.4130 3.8561 1.3302 0 3 1 0.0 1.0 0.38 0.000227 0.001929 0.0111 0.05 0.1703 0.369 0.4035 0.1426 -0.0052 -0.0679 -0.1319 0.2576 0.6357 0.2838 0.0086 0.0609 0.2135 0.3944 0.3973 0.2586 0.0124 -0.2218 -0.8713 1.0285 -0.018 -0.08 0.2089 1.255 1.0 1.0 1.0 1.0 1.0 1.0 0.0405 0.2022 0.4338 0.4897 1.0 K. Doll, Surf. Sci. 544, 103-120 (2003) note: calibrated for Ni metal - for a system where Ni is positively charged, it may be necessary to remove the outermost diffuse sp exponent, or shift it to a higher value, possibly reoptimise. Silver 247 9 INPUT 19. 0 2 2 2 2 0 13.130000 6.510000 11.740000 6.200000 10.210000 4.380000 14.220000 7.110000 0 0 3 2.0 1.0 9.08844 7.54073 2.79401 0 0 1 1.0 1.0 1.48016 0 0 1 0.0 1.0 0.63 0 0 1 0.0 1.0 0.11 0 2 2 6.0 1.0 4.45124 3.67526 0 2 2 0.0 1.0 1.29129 0.65258 0 2 1 0.0 1.0 0.23000 0 3 4 10.0 1.0 7.99473 2.78477 1.20974 0.50539 0 3 1 0.0 1.0 0.18 255.139365 36.866122 182.181869 30.357751 73.719261 12.502117 -33.689920 -5.531120 0 0 0 0 0 0 0 0 -1.964813 2.733219 0.199115 1.000000 1.000000 1.000000 -6.083378 6.416854 0.753974 0.273060 1.000000 -0.016388 0.281411 0.486326 0.386726 1.000000 K. Doll and N. M. Harrison, Phys. Rev. B 63, 165410 (2001) based on the pseudopotential and basis set from: D. Andrae, U. Häussermann, M. Dolg, H. Stoll, and H. Preuss, Theor. Chim. Acta 77, 123 (1990) note: calibrated for Ag metal - for a system where Ag is positively charged, it may be necessary to remove the outermost diffuse exponents, or shift them to higher values, possibly reoptimise Platinum 278 9 INPUT 18 1 3 3 3 0 0 3.309569 13.428651 6.714326 3.309569 10.365944 5.182972 3.309569 7.600479 3.800240 3.309569 0 0 3 2.0 1.0 16.5595630 13.8924400 5.8536080 0 0 1 0.0 1.0 1.2873200 0 0 1 0.0 1.0 0.59 0 1 1 0.0 1.0 0.11 0 2 2 6.0 1.0 7.9251750 7.3415380 0 2 2 0.0 1.0 1.9125150 1.0715450 0 2 1 0.0 1.0 0.4379170 0 3 4 10.0 1.0 3.9395310 3.5877770 1.2862310 0.5198140 0 3 1 0.0 1.0 0.167 24.314376 579.223861 29.669491 -24.314376 280.860774 26.745382 -24.314376 120.396444 15.810921 -24.314376 0 0 0 0 0 0 0 0 0 0 -0.8849447 1.5011228 -1.5529012 1. 1. 1.0 1.0 4.9530757 -5.8982100 0.3047425 0.7164894 1.0 -0.5826439 0.5922576 0.4736921 0.5765202 1.0 K. Doll, Surface Science 573, 464-473 (2004). based on the pseudopotential and basis set from: D. Andrae, U. Häussermann, M. Dolg, H. Stoll, and H. Preuss, Theor. Chim. Acta 77, 123 (1990) note: calibrated for Pt metal - for a system where Pt is positively charged, it may be necessary to remove the outermost diffuse exponents, or shift them to higher values, possibly reoptimise
© Copyright 2026 Paperzz