Theoretical study on the molecular interaction between small ammonia nanotubes and coinage metals

Contents

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Chapter 1

Introduction

1-1)Ammonia

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1-2)Ammonia clusters

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1-3)Nanotubes

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1-4)Objective of the present research

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Chapter 2

Literature review

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Chapter 3

Theoretical background

3-1)Ab initio methods

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3-2)Density functional theory(DFT)

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3-3)Basis set

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3-4)Basis set superposition errors(BSSEs)

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3-5)Counterpoise correction including monomer deformation

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3-6)Theory of atoms in molecules(AIM)

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3-7)Natural bond orbital(NBO)

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3-8)The pseudopotential approximation

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3-9)Computational details of the present research

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Chapter 4

Results and discussion

4-1)Ammonia nanotubes

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4-1-1)Structure of ammonia nanotubes

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4-1-2)Energetics of ammonia nanotubes

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4-1-3)AIM analysis of ammonia nanotubes

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4-2)Interaction of coinage metals with ammonia nanotubes

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4-2-1) Geometrical structures

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4-2-2)Energy of interaction with coinage metals

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4-2-3)AIM analysis of the complexes between ammonia nanotubes and

         Coinage metals

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4-2-4)Natural bond orbital (NBO) analysis

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4-3)Conclusion

References

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Tables

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Table 4-1.d_intra , H-bond distances in layers; .d_inter , H-bond distances between  layers;

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Table4-2.CalculatedStabilization Energies (SE) and Inter-Ring Stabilization Energies (IRSE) for obtained ammonia nanotubes.

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Table 4-3.AIM topological parameters:ρ, electron density;∇²ρ, Laplacian; at M062X/TZV level of  calculation.

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Table 4-4. H-bond Strength (Δ_com) at theM062X/TZV  level  of  calculation.

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Table 4-5. Bond distance between nitrogen and metal (R_N-M); bond angleof  hydrogen-nitrogen-metal  ( H-N-M).

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Table 4-6.Binding energy(ΔE_bind), BSSEs, deformation energy (E_def) and corrected interaction energy( at M062X/TZV level of calculation

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Table4.7. Topological parameters at BCP of N-M (M=Cu, Ag, Au) calculated at M062X/TZV level. Parameters:ρ(r), electron density; ,Laplacian; H(r), electron energy density;  and|V(r)|/G(r), ratio of potential to kinetic electron energy density.

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Table 4-8. Charge transfer (CT)  and NBO second-order interaction energy (E ⁽²⁾ )  for the corresponding donor-acceptor orbital interactions of copper with ammonia  nanotubes calculated at M062Xlevel.

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Table 4-9. Charge transfer (CT)  and NBO second-order interaction energy (E ⁽²⁾ )  for the corresponding donor-acceptor orbital interactions of silver with ammonia  nanotubes calculated at M062X level.

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Table 4-10. Charge transfer (CT)  and NBO second-order interaction energy (E ⁽²⁾ ) for the  corresponding donor-acceptor orbital interactions of gold with ammonia nanotubescalculated at M062X level.

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Figures

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Figure 4-1.Optimized geometries ofk-(NH3)₄,k=1,2,3 nanotubes at M062X/TZVlevel. The dotted line represents the N-H….N  hydrogen bond.

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Figure 4-2.Optimized geometries of  k-(NH3)₅, k=1,2,3  nanotubes at M062X/TZV level. The dotted line represents  the N-H….N  hydrogen bond.

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Figure 4-3.Calculated correctedSEs for k-(NH₃)_n nanotubes.

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Figure 4-4.Calculated correctedIRSEs for k-(NH₃)_n nanotubes.

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Figure 4-5.Optimized geometriesforthe interaction of coinage metals (M=Cu,Ag,Au) with  k-(NH₃)₄ nanotubes.

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Figure 4-6.Optimized geometries for the interaction of coinage metals (M=Cu, Ag, Au) with k-(NH₃)₅nanotubes.

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Figure 4-7.Calculated interaction energy of k-(NH₃)₄nanotubes, with M=Cu, Ag, Au.

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Figure 4-8.Calculated interaction energy of k-(NH₃)₅ nanotubes,  with M=Cu, Ag, Au.

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Figure 4-9. Calculated electron densityρ(r) at BCP of contact distance for

interaction of coinage metals with  k-(NH₃)₄  nanotubes.

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Figure 4-10.Calculated electron densityρ(r)at BCP of contact distance for

interaction of coinage metals with  k-(NH₃)₅  nanotubes.

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