In Mark's own words:

"Some people collect stamps. I collect chemical species and study their interactions & reactions.

"I use a MySQL relational database – called The Chemical Thesaurus Reaction Chemistry Database, available online at www.chemthes.com – to store, sort, classify and slice 'n' dice information about chemical entities and the interactions and reactions they undergo.

"Against this solid, data driven background, I have studied the ideas of Mendeleeve, Lewis, Pauling, Ingold, Hückel, Pearson, Jørgensen, Fukui, Klopman, Woodward & Hoffmann, Olah, Scerri and others...

"Using software tools – spreadsheets & relational databases – and taking a combinatorial and systems approach, I explore the reaction chemistry space close to the periodic table of the elements.

"I look at the main group binary compounds in terms of van Arkel-Ketelaar triangles & Laing tetrahedra of structure, bonding and material type. I use hydrogen probe experiments to find objects & patterns in reaction chemistry space, including: congeneric arrays, the five reaction chemistries, the Lewis acid/base interaction matrix and the mechanism matrix. At the same time, I explore 'Chemistry, The Whole Thing' in terms of complexity and the nature of structural theory.

"I seem to be filling part of the scientific story between the periodic table and the established disciplines of organic and inorganic chemistry, an area that is poorly covered by traditional texts. I call this science "chemogenesis", as it deals with the emergence of mechanism and chemical reactivity.

"Please realize that the Chemogenesis Webbook is a completely new chemistry text. For the first time reaction chemical structure & reactivity is presented as a linear narrative, rather than as a collection of tenuously connected factoids. Indeed, I suggest that the chemogenesis web book is the chemistry textbook unmuddled.

"The Chemogenesis Webbook is also a new type of textbook in that it is dynamic. The ChemThes reaction chemistry database engine is used to drive interactive web pages such as the Binary Material, Thermochemistry, Redox Chemistry & Addition Synthlets, mini-applications written in MySQL/PHP/Java script that make predictions about chemical structure & reactivity.

"Indeed, at all times the chemogenesis analysis is backed by the rigour and beauty of the relational schema that lies behind The Chemical Thesaurus reaction chemistry database."

Mark R Leach Ph.D.

Read more in a (2006) interview with Mark Leach in Reactive Reports.

June The 8th Theory: Independent congeneric series

H3C–	H2N–	HO–	F–
H3N:	H2O:	HF:	Ne:

1989-1999
The PNG Decade

Move from spreadsheets to mapping chem data with a relational database.
Extensive use of ab initio chemistry software.
Separate ideas about chemistry from chemistry data.
All reactions are changes in phase space, and changes in phase space can be mapped to an elegant RDMS schema.
Map processes that can be expressed as a chemical equation of the type:
       A   →   B
       X   +   Y   →   Z
       etc.
Enter reaction chemistry data from all branches of chemistry.
Develop software synthlets utilising reaction chemistry data.

The Chemical Thesaurus 1.0, Helix Express RDMS: Publication.