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Congeneric Array Interactions

Congeneric arrays –sets of chemical species with linear structure and reactivity behaviour traits –can react with each other to produce new arrays which are also congeneric.

Congeneric Array Interaction Algebra

Congeneric interactions follow the usual rules of array algebra:

(1 x 1) x (1 x 1)
( 1 x 1)
dot x dot
(5 x 1) x (1 x 1)
( 5x 1)
series x dot
(4 x 4) x (1 x 1)
( 4 x 4)
planar x dot
(5 x 1) x (4 x 1)
( 5 x 4)
series x series
(5 x 1) x (4 x 4)
( 5 x 4 x 4)
series x planar

For example, the proton x hydride ion (a dot x dot interaction) gives H2, a congeneric dot. Here is no other chemical species at all like H2 (other than its isotopic homologs D2, T2, HD, etc.):

(1 x 1) x (1 x 1)
( 1 x 1)
H+ + H

Likewise, the Group 1 cations vs. the hydride ion (a series x dot interaction) gives rise to the Group 1 saline hydrides (a series).

(H)   x   (Li+, Na+, K+, Rb+, Cs+)   →   (LiH, NaH, KH, RbH, CsH)

We have already seen these interactions with the hydrogen probe experiments, but the logic can be continued to generate a range of ionic and polar covalent materials.

We shall explore three (series x series) interactions to generate corresponding congeneric planars:

In each of these three cases, the congeneric planars are quantified with respect to the % ionic character of the formed bond as determined by the Pauling equation, here. This bond character is colour coded.

The (5 x 1) x (4 x 4) Congeneric Array Interaction: A Congeneric Volume

The logic of congeneric array interaction can be continued to produce a congeneric volume:

(5 x 1) x (4 x 4)
( 5 x 4 x 4)
series x planar

One such congeneric volume is discovered when the Group 1 cations, Li+ to Cs+, are arranged against the anionic Lewis bases of the type H3C , F and I.

The resulting congeneric volume has regular changing bond polarisation properties over the volume:

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Ligand Replacement Congeneric Series The Emergence of Organic Chemistry

© Mark R. Leach 1999 –

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