Electronic Properties of Atoms

Although we have not yet described the modem methods of dealing with theoretical chemistry (quantum mechanics), it is possible to describe many of the properties of atoms. For example, the energy necessary to remove an electron from a hydrogen atom (the ionization energy or ionization potential) is the energy that is equivalent to the series limit of the Lyman series. Therefore, atomic spectroscopy is one way to determine ionization potentials for atoms. 

Several facts are apparent from this graph. Although we have not yet dealt with the topic of electron configuration of atoms, you should be somewhat familiar with this topic from earlier chemistry courses. We will make use of some of the ideas that deal with electron shells here but delay presenting the details until later. 

The helium atom has the highest ionization potential of any atom. It has a nuclear charge of + 2, and the electrons reside in the lowest energy level close to the nucleus. 

The noble gases have the highest ionization potentials of any atoms in their respective periods. Electrons in these atoms are held in shells that are completely filled. 

---

Bohr s atomic model was the first to successfully account for electronic properties of atoms, specifically, the interaction of atoms and light (spectroscopy). 

In practice, it is found that the electronic properties of atomic and molecular systems can be understood only if the second alternative is true. This leads to a more fundamental statement of the Pauli exclusion principle as ... 

In this section a recapitulatory description of the most common ah initio and density functional approaches will be presented. Ah initio methods calculate the electron properties of atoms and molecules at the absolute temperature (T = 0). The starting point is in most cases the non-relativistic Schrodinger equation... 

---