Test phase, structure elucidation

Even if improved hardware and/or software is feasible for the "generate" and/or "test" phases of structure elucidation, it would appear that improvements in the first phase for derivation of structure information could substantially reduce the effort required for these latter two phases, and similarly increase the proportion of unknowns for which the interpreter can derive a satisfactory answer only aided by STIRS. (The availability of infrared absorption data from GC/IR/MS would be particularly helpful.)... 

This phase saw continuous advances in chemistry and medicine. Organic chemistry was now capable of the synthesis of relatively complex targets by multistep sequences. The concept of systematically preparing a compound series and testing it for a biological effect became common, as exemplified in Ehrlich s quest for antisyphilitic agents. More and more pure natural products were identified and their structures elucidated. Synthetic mimics became a reahty. For example, amphetamines were inspired by the natnral prodnct lead, ephedrine. 

As early as 1938, Langmuir observed the phase separation of clay suspensions into an isotropic phase and a birefringent gel at the macroscopic level in test-tubes [9]. However, in the same report, he noted that this property of phase separation was gradually lost with time, which he tentatively explained by the incorporation of impurities diffusing from the glass tubes. He also compared this system to normal liquid crystals. Later, in 1956, Emerson observed a banded texture similar to that displayed by the Tobacco Mosaic Virus [48]. The investigation of clay suspensions from the structural point of view has been recently resumed. However, the study of the nematic order of suspensions of montmorillonite clays is in fact complicated by their gel properties. In spite of sustained efforts to understand its nature, the gelation mechanism has not yet been fully elucidated [49]. 

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