The Indaba Story
“INDABA” is an African term used to describe a meeting to analyze a difficult problem from all angles.
The venue for the first four Indabas was Skukuza - the headquarters rest camp in the Kruger National Park, South Africa. Indaba 5 and 6 were held at the Berg-en-Dal rest camp in the South of the Kruger Park.
The themes of the Indaba series take a multidisciplined approach to various aspects related to molecular structure:
INDABA 1, 20 - 25 August 1995: "Fundamental Principles of Molecular Modeling". Small-molecule crystallography and molecular mechanics are the appropriate techniques for the study of molecular shapes, whereas electron-density and quantum-mechanical modeling provide the link with material properties. This is not an historical accident, but a dictum of basic theory. Molecules, as entities with both classical and non-classical character, exist at the quantum limit. The workshop is aimed at discourse around this very subtle issue, in an effort to analyze questions related to the reality of molecules, an understanding of their electronic properties, and the effects of a chemical or crystal environment. The main theme of the workshop will be the relationship between experimental observations and theoretical interpretation. Hands-on demonstration of important molecular modeling and graphics packages and on-line use of the Cambridge Structural Database will be a special feature. Indaba 1 website.
INDABA 2, 3 - 8 August 1997: "Molecular Interactions". The idea of intermolecular interactions relates to the notion that materials in the bulk consist of weakly interacting units, or molecules, in the sense that intramolecular interactions are stronger than these, by orders of magnitude. In view of this it is argued that, by ignoring the weak interactions, the same molecular units that occur in the gas phase can be recognized in condensed phases. At the same time it is commonly accepted that solid materials exhibit many properties not apparent in other phases and acquired as a result of intermolecular interactions only. From both points of view the concept is rather ill-defined and of questionable importance. The problem relates to the model of choice to describe condensed phases. Defined as single quantum-mechanical systems there is no basis to distinguish between intra- and intermolecular forces. An intermolecular interaction is then defined only for the gas phase, where it is practically negligible in any case. An attempt to distinguish between intra- and intermolecular interactions necessarily fails to recognize their interdependence and creates artifacts to be used later on as independent concepts, in terms of which to explain chemical behavior. In terms of deformation electron densities in crystals the distinction becomes even more vague and the definition of molecular units even more arbitrary. Answers to these questions are probably not simple and different points of view can surely be formulated in all cases. Indaba 2 website. See also the IUCr 1997 Report - Commission on Structural Chemistry.
INDABA 3, 6 - 11 August 2000: "Symmetry and Structure: Symmetry Breaking, Chirality and Disorder in Molecules and Crystals". In current science, symmetry is widely considered to be one of the most fundamental concepts, either by reference to the structure of space-time or alternatively, the laws of physics. In an achiral world the laws of physics are time-reversible and in a chiral world they are not. These considerations pose a number of important questions, starting from, how chiral is the world? What are the implications of chiral space? Why does only one law of nature appear to be temporally irreversible? What causes the spontaneous lowering of symmetry? Why are some crystals chiral and others are not? Is mathematically exact symmetry possible in the real world? What is the role of the environment? Indaba 3 website. See also the meeting report and IUCrSC report
INDABA 4, 17 - 22 August 2003: "Patterns in Nature"; covered topics such as Symmetries, Hidden or Broken Symmetries, Structural Relationships, Aperiodic Crystals, Incommensurate Structures, Periodic relationships amongst atoms, nuclides and homologous series, Fractals, Chaos, Critical Phenomena, Numerical Patterns, etc. Indaba 4 website.
INDABA 5, 20 - 25 August 2006: "Models, Mysteries and Magic of Molecules"; covered the progress that is being made to achieve first-principle understanding of molecular science: structure and dynamics (that include bonding), activity and function. The symposium will be directed at all molecular scientists from chemistry, biology, physics, materials science and related fields such as crystallography, spectroscopy, catalysis and others. Special topics for discussion include nanomaterials, pharmaceuticals, polymorphism, supermolecules, disorder in crystals, novel geological niches, electron density and other marvels and myths, related to the manufacture of molecules. Indaba 5 website.
INDABA 6, 30 August – 4 September 2009: "Structure and Properties"; The discovery of novel molecular compounds and materials with exciting properties is often to a large extent based on serendipity and to another on the careful observation and interpretation of experimental data with classical models such as approaches derived from qualitative molecular orbital theory, methods based on parameters related to donor-acceptor strengths or empirical concepts based on geometric and steric effects. For compounds with novel and exciting properties, a subsequent thorough analysis of experimental data - state-of-the- art spectroscopy, magnetism, thermodynamic properties and/or detailed mechanistic information - with sophisticated electronic structure calculations is performed to interpret the experimental data and fully understand the novel compounds. As a result, new models and theories may emerge, possibly leading to rules concerning how the relevant properties of the new class of compounds may be improved. Indaba 6 website.