In recent years, the processing order during the synthesis of new chemical compounds has been redefined. Until now a chemist considered primarily receiving a new compound and only then searched for its potential application. The new philosophy of proceedings forces chemists to answer the question: what physical and chemical properties a new chemical compound must have, and what should be structured. After that it has to be planned how to get the compound including the defined budget. The compounds obtained by conventional chemical synthesis are then used to create new functional materials having the properties as scheduled. The paper presents the way of the proceedings from a molecular receptor to a new nanomaterial containing this receptor, so in other words from individual molecules to new material with specific and previously planned properties.
The complex formation for two different groups of cyclic polyamines with four or six nitrogen atoms and with pendant-arm modification and silver(I) ions in propylene carbonate has been studied by electron spray ionization mass spectrometry (ESI MS), potentiometric and Austin Model 1 (AM1d) semiempirical methods. The stability constants of complexes are determined by potentiometric method. The structure of those complexes are visualised by AM1d semiempirical calculations.
The thermal behaviour of the giant molybdenum ring cluster compound formula - containing H2O ligands partly substituted by methanol molecules - was studied using TG, DTG and DTA analyses simultaneously, and mass spectromet-ric analysis of the decomposition products. Methanol is released from the sample quite rapidly even at room temperature (and even before the experiments start) but small traces of methanol are still present which we tried to use for characterising the different stages of giant ring transformation. The initial rapid loss of mass of the sample was accompanied by the DTA and DTG peak at 75°C. A small DTA endothermic peak at 165°C was assigned to an MS maximum indicating the increased emission of methanol and formaldehyde. Double exothermic peaks at 352 and 366° C corresponded to the loss of water formed from the abundant OH groups. Simultaneously, peaks indicating trace emission of formaldehyde, methanol, carbon dioxide as well as traces of hydrocarbons containing 2-4 carbon atoms per molecule were registered mass spectrometrically. The exothermic effect was attributed to a kind of "recrystallisation" process of the completely dehydrated product.
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