5.3: quantum mechanics and the wave nature of matter

the wave nature of matter

  • Louis De Broglie theorized that if light can have material properties, matter should exhibit wave properties, developing the slit experiment to create a new model of the atom
  • electrons move trough “slits”
      * a particle can only move through one slit at a time
      * a wave can move through multiple slits at a time

the quantum mechanical model of the atom

  • electronic structure: the structure of electrons within an atom

  • Louis De Broglie, Edward Schrödinger, and Werner Heisenberg were on the front line of the development of quantum mechanics

  • quantum mechanics (aka wave mechanics) was a completely new approach to the atomic model

quantum mechanics

  • Schrödinger’s equation: Ĥψ = Eψ
      * ψ = wave function
      * E = total energy of the atom
  • each solution to Schrödinger’s equation is a probability of where an electron could be found in space
  • the wave function is a function of the coordinates x, y, and z
  • orbital: a solution to the wave function
      * orbitals are not the same as Bohr orbits
      * 1s orbital: the wave function corresponding to the lowest energy for the hydrogen atom
      * s orbital: a spherical orbital contained by every energy level → volume changes by level but shape does not
      * p orbital: an orbital consisting of two lobes contained by the second energy level and up
      * d orbital: an orbital that generally contains four lobes contained by the third energy level and up
  • orbitals are essentially regions of space in which the probability of finding an electron is ≥ 90%
  • heavily correlated to nuclear charge and ionization energy
      * nuclear charge is determined by the size of ions and properties of the atom
      * ionization energy describes the minimum amount of energy required to remove an electron from the ground state of a gaseous atom or ion, and requires more energy to remove each successive electron from the atom
      * ground state: the lowest-energy state of an atom
      * excited state: higher-energy states of an atom (n ≥ 2)