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)