Surface effects in the hydrogen atom confined by dihedral angles

This chapter reports on some of the remarkable surface effects in the hydrogen atom under confinement by dihedral angles, in comparison with the familiar properties of the atom in its free configuration, due to the breaking of the O(2) symmetry for rotations around the common edge of the angles. In fact, by modelling the confinement with the boundary condition that the electronic wavefunction vanishes at the half-planes defining the dihedral angles, it follows that: (i) the degeneracy of the energy levels of the hydrogen eigenfunctions depends on the value of the confining angle, (ii) the probability of finding the electron at the position of the nucleus vanishes, with the consequent suppression of the Fermi-contact interaction hyperfine structure, and its replacement with the proton and electron magnetic moment interaction quadrupole hyperfine structure, (iii) the atom acquires an electric dipole moment, thus exhibiting an additional reactivity, (iv) its electron exerts a well-defined pressure distribution on the walls of the confining dihedral angle, and (v) the Zeeman effect for a uniform magnetic field in the direction of the edge of the angles is also different from that of the free atom. As a consequence of (i), it is expected that the many-electron atoms of the successive chemical elements under the same situations of confinement will show periodic properties different from the familiar ones in their free configurations. Hopefully there will be experimental works putting to the test some of the above and other theoretical predictions presented herein.