1;Computational Studies of Transition Metal Nanoalloys;4 2;Supervisor's Foreword;8 3;Acknowledgments;9 4;Contents;10 5;1 Introduction;14 5.1;1.1...Clusters: Overview and Applications;15 5.2;1.2...Nanoalloys;16 5.2.1;1.2.1 Homotops;17 5.2.2;1.2.2 Segregation in Nanoalloys;17 5.3;1.3...Experimental Background: From Synthesis to Cluster Characterisation;19 5.4;1.4...Second and Third Rows Transition Metal Nanoalloys;20 5.4.1;1.4.1 Pd--Pt Clusters;20 5.4.2;1.4.2 Pd--Au Clusters;21 5.4.3;1.4.3 Ag--Pt Clusters;21 5.4.4;1.4.4 Ag--Au Clusters;22 5.5;1.5...Chemisorption on Single Metal and Bimetallic Clusters;22 5.6;References;24 6;2 Theoretical Background and Methodology;27 6.1;2.1...Modelling Metal Clusters and Nanoalloys;27 6.1.1;2.1.1 Potential Energy Surfaces;28 6.2;2.2...Theoretical Methods;28 6.2.1;2.2.1 The Gupta Potential;28 6.2.2;2.2.2 Early Density Functional Theory: Thomas Fermi Model;29 6.2.3;2.2.3 Modern Density Functional Theory;31 6.2.4;2.2.4 Functionals and Basis Sets;34 6.3;2.3...Global Optimization Techniques;35 6.3.1;2.3.1 The Birmingham Cluster Genetic Algorithm;35 6.3.2;2.3.2 The Basin-Hopping Monte Carlo Algorithpotential energy surface (PES)m;38 6.3.3;2.3.3 Shell Optimization Routine;39 6.3.4;2.3.4 Combined EP-DFT Approach;39 6.4;2.4...Energetic Analysis;40 6.5;References;42 7;3 34-Atom Pd--Pt Clusters;44 7.1;3.1...Introduction;44 7.2;3.2...Computational Details;44 7.3;3.3...Results and Discussion;45 7.3.1;3.3.1 Gupta Potential Calculations on PdmPt34&!nbsp;minus&!nbsp;m;45 7.4;3.4...DFT Calculations;48 7.4.1;3.4.1 Composition Pd24Pt10;49 7.4.2;3.4.2 Segregation Effects for Pd17Pt17 Clusters;51 7.4.3;3.4.3 Analysis of the Dh--cp(DT) Structure;52 7.4.4;3.4.4 Conclusions;54 7.5;References;55 8;4 98-Atom Pd--Pt Nanoalloys;56 8.1;4.1...Introduction;56 8.2;4.2...Computational Details;56 8.3;4.3...Results and Discussion;57 8.3.1;4.3.1 Comparison of Global Minimum Structures for 98-Atom Pd--Pt Nanoalloys;57 8.3.2;4.3.2 Analysis of the Leary Tetrahedron;61 8.3.3;4.3.3 Onion-Like Structures;62 8.3.4;4.3.4 Competition Between Different Structural Families;62 8.4;4.4...Conclusions;63 8.5;References;64 9;5 38-Atom Binary Clusters;65 9.1;5.1...Introduction;65 9.2;5.2...Computational Details;67 9.3;5.3...Results and Discussion;68 9.3.1;5.3.1 Structural Families;69 9.3.2;5.3.2 Composition Dependence of the Mixing Energy;72 9.3.3;5.3.3 Pd--Pt Clusters;72 9.3.4;5.3.4 Segregation Effects in Pd--Pt Clusters;74 9.3.5;5.3.5 Ag--Pt Clusters;75 9.3.6;5.3.6 Segregation Effects in Ag--Pt Clusters;75 9.3.7;5.3.7 Pd--Au Clusters at Compositions 14--24 and 6--32;76 9.3.8;5.3.8 Pd--Au Clusters at Compositions 24--14 and 32--6;78 9.3.9;5.3.9 Segregation Effects in Pd--Au Clusters;79 9.3.10;5.3.10 Ag--Au Clusters;79 9.3.11;5.3.11 Segregation Effects in Ag--Au Clusters;81 9.4;5.4...Conclusions;84 9.5;References;85 10;6 Chemical Ordering of 34-Atom Pd--Pt Nanoalloys;87 10.1;6.1...Introduction;87 10.2;6.2...Computational Details;90 10.2.1;6.2.1 Genetic Algorithm;90 10.3;6.3...Results and Discussion;92 10.3.1;6.3.1 DFT Study of (Pd--Pt)N/2 Clusters (N = 2--20);92 10.3.2;6.3.2 Gupta Potential Study of (Pd--Pt)N/2 Clusters (N = 2--20) for Potentials Ia, Ib and Ic;95 10.3.3;6.3.3 Gupta Potential Study of 34-Atom Pd34Pt34minusm Clusters for Potentials Ia, Ib and Ic;95 10.3.4;6.3.4 Detailed Study of 34-Atom PdmPt34minusm Clusters for Variable Gupta Potential Weights;98 10.3.5;6.3.5 Structural Motifs;99 10.3.6;6.3.6 Segregation;104 10.3.7;6.3.7 Study of Interfacial Areas in Segregated Bimetallic Clusters;104 10.3.8;6.3.8 Derivation of the Interfacial Area Formulae;107 10.3.8.1;6.3.8.1 Core--Shell Segregation;107 10.3.8.2;6.3.8.2 Spherical Cap Segregation;108 10.3.8.3;6.3.8.3 Ratio of Interfacial Areas;109 10.4;6.4...Conclusions;109 10.5;References;111 11;7 Theoretical Study of Pd--Au Clusters;112 11.1;7.1...Introduction;112 11.2;7.2...Computational Details;113 11.2.1;7.2.1 Genetic Algorithm;113 11.2.2;7.2.2 Pd--Au Parameters;113 11.3;7.3...Results and D