Eur. Phys. J. D (2013) 67: 165
DOI: 10.1140/epjd/e2013-40257-4
Effect of CO and H adsorption on the compositional structure of
binary nanoalloys via DFT modelling
Supplementary Material
Paul S. West1, Roy L. Johnston1*, Giovanni Barcaro2, Alessandro Fortunelli2*
1
2
School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT,
United Kingdom
CNR-IPCF, Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche,
Molecular Modeling Laboratory, Via Moruzzi 1, 56124, Pisa, Italy
Interaction energies per CO molecule (Ei) are calculated using the formula:
Ei =
Eclust − Ebare − XECO
X
where Eclust is the total energy of the cluster (both in absence and in presence of a X number of CO
molecules adsorbed), Ebare is the energy of the cluster without molecules adsorbed on its surface
and ECO is the energy of the CO molecule. This formula is given in explicit form for CO, but holds
with appropriate modifications for adsorption of H atoms.
Figures S1 and S2 show the interaction energies as a function of the number of CO molecules and H
atoms adsorbed on the AuPd, PdPt, CuPt and PdRh systems, respectively.
*
*
Corresponding author: [email protected]
Corresponding author: [email protected]
Eint- Au6Pd32CO(x)
0,0
Eint- Pd6Au32CO(x)
0,0
-0,5
-0,5
Cent
Core
Hex
-1,0
Cent
Core
Hex
-1,0
-1,5
-2,0
-1,5
1
2
3
5
4
6
8
7
1
2
3
4
(a)
6
7
8
(b)
Eint- Pd6Pt32CO(x)
0,0
5
Cent
Core
Hex
-0,5
Eint- Pt6Pd32CO(x)
0,0
Cent
Core
Hex
-0,5
-1,0
-1,0
-1,5
-1,5
-2,0
-2,0
-2,5
1
2
3
4
5
6
7
1
8
2
3
4
(c)
6
7
8
(d)
Eint Cu6Pt32CO(x)
0,0
5
Eint- Pt6Cu32CO(x)
0,0
-0,5
Cent
Core
Hex
-0,5
-1,0
-1,0
-1,5
Cent
Core
Hex
-2,0
-1,5
-2,5
-2,0
1
2
3
4
5
6
7
8
1
2
3
(e)
4
5
6
7
8
(f)
Eint Rh6Pd32CO(x)
Eint Pd6Rh32CO(x)
0,0
0,0
Cent
Cent
-0,5
Core
-0,5
Core
Hex
Hex
-1,0
-1,0
-1,5
-1,5
-2,0
-2,0
-2,5
-2,5
1
2
3
4
5
6
7
8
1
2
3
(g)
4
5
6
7
8
(h)
Figure S1. Interaction energies per CO molecule (in eV) on the eight compositions investigated, as a function
of the number of CO ligands attached to the surface. The blue lines refer to the cent configuration, the green
ones to the core configuration and the red ones to the hex configuration.
Eint - Au6Pd32H(x)
0,0
Eint - Pd6Au32H(x)
0,0
Cent
Core
Hex
-0,5
-1,0
Cent
Core
Hex
-0,5
-1,0
-1,5
-1,5
-2,0
-2,0
-2,5
-3,0
-2,5
1
2
3
4
5
6
7
8
1
2
3
4
(a)
5
6
7
8
(b)
Eint - Pt6Pd32H(x)
Eint - Pd6Pt32H(x)
0,0
0,0
Cent
Core
Hex
-0,5
-1,0
Cent
Core
Hex
-0,5
-1,0
-1,5
-1,5
-2,0
-2,0
-2,5
-2,5
-3,0
-3,0
-3,5
1
2
3
4
5
6
7
1
8
2
3
(c)
4
5
6
7
8
(d)
Eint - Cu6Pt32H(x)
Eint - Pt6Cu32H(x)
0,0
0,0
Cent
Core
Hex
-0,5
-1,0
Cent
Core
Hex
-0,5
-1,0
-1,5
-1,5
-2,0
-2,0
-2,5
-2,5
-3,0
-3,5
-3,0
1
2
3
4
5
6
7
8
1
2
3
(e)
4
5
6
7
8
(f)
Eint - Rh6Pd32H(x)
Eint - Pd6Rh32H(x)
0,0
0,0
Cent
Core
Hex
-0,5
Cent
Core
Hex
-0,5
-1,0
-1,0
-1,5
-1,5
-2,0
-2,0
-2,5
-2,5
-3,0
-3,0
1
2
3
4
5
6
7
8
1
(g)
2
3
4
5
6
7
8
(h)
Figure S2. Interaction energies per H atom (in eV) on the eight compositions investigated, as a function of
the number of H ligands attached to the surface. The blue lines refer to the cent configuration, the green ones
to the core configuration and the red ones to the hex configuration.