TITLE:
Coherence of the Even-Odd Rule with an Effective-Valence Isoelectronicity Rule for Chemical Structural Formulas: Application to Known and Unknown Single-Covalent-Bonded Compounds
AUTHORS:
Geoffroy Auvert
KEYWORDS:
Isoelectronicity, Effective Valence, Molecule, Ion, Even-Odd, Rule, Structural Formula, Covalent Bond
JOURNAL NAME:
Open Journal of Physical Chemistry,
Vol.4 No.3,
August
6,
2014
ABSTRACT: Ions or molecules are said
to be isoelectronic if they are composed of different elements but have the
same number of electrons, the same number of covalent bonds and the same
structure. This criterion is unfortunately not sufficient to ensure that a
chemical structure is a valid chemical compound. In a previous article, a
procedure has been described to draw 2D valid structural formulas: the even-odd
rule. This rule has been applied first to single-bonded molecules then to
single-charged single-bonded ions. It covers hypovalent, hypervalent or classic
Lewis’ octet compounds. The funding principle of the even-odd rule is that each
atom of the compound possesses an outer-shell filled only with pairs of
electrons. The application of this rule guarantees validity of any
single-covalent-bond chemical structure. In the present paper, this even-odd
rule and its electron-pair criterion are checked for coherence with an
effective-valence isoelectronic rule using numerous known compounds having
single-covalent-bond connections. The test addresses Lewis’ octet ions or
molecules as well as hypovalent and hypervalent compounds. The article
concludes that the even-odd rule and the effective-valence isoelectronicity
rule are coherent for known single-covalent-bond chemical compounds.