For simulating hydrophobic−amphiphilic (HA) copolymers, we have developed a “side-chain” HA model in which hydrophilic (P) interaction sites are attached to hydrophobic (H) main chain, thereby forming amphiphilic (A) monomer units, each with dualistic (hydrophobic/hydrophilic) properties. Using this coarse-grained model, we performed molecular dynamics simulations of the hydrophobically driven self-assembly in a selective solvent, for both single-chain and multichain systems. The focus is on the regime in which H and P interaction sites are strongly segregated. Single-chain simulations are performed for copolymers with the same HA composition but with different distribution of H and A monomer units along the hydrophobic backbone, including regular copolymers comprising H and A units in alternating sequence, (HA) x , regular multiblock copolymers (H L A L ) x composed of H and A blocks of equal lengths L = 3, and quasi-random proteinlike copolymers having quenched primary structure. In a solvent selectively poor for H sites, the proteinlike polyamphiphiles can readily adopt spherical-shaped compact conformations with the hydrophobic chain sections clustered at the globular core and the hydrophilic groups forming the envelope of this core and buffering it from solvent. Because of the fact that these globules are size- and shape-persistent objects, they maintain their morphological integrity even in rather concentrated solutions where no large-scale aggregation is observed. Moreover, we find that the population of aggregates generally decreases with worsening solvent quality. The compact conformations of long regular copolymers tend to be strongly elongated in one direction.

Computer simulation modelling of a flexible comb copolymer with attractive interactions between the monomer units of the side chains is performed. The conditions for the coil‐globule transition, induced by the increase of attractive interaction, ε, between side chain monomer units, are analysed for different values of the number of monomer units in the backbone, N, in the side chains, n, and between successive grafting points, m. It is shown that the coil‐globule transition of such a copolymer corresponds to a first‐order phase transition. The energy of attraction (ε) required for the realisation of the coil‐globule transition decreases with increasing n and decreasing m. The coil‐globule transition is accompanied by significant aggregation of side chain units. The resulting globule has a complex structure. In the case of a relatively short backbone (small value of N), the globule consists of a spherical core formed by side chains and an enveloping shell formed by the monomer units of the backbone. In the case of long copolymers (large value of N), the side chains form several spherical micelles while the backbone is wrapped on the surfaces of these micelles and between them.

Theoretical and experimental investigations are made of magnetooptical activity (MOA) of (parity) forbidden intraconfigurational4f-4f transitions in Er(PO,), rare-earth paramagnetic phosphate glasses. The interpretation of magnetooptical spectra in frames of a theoretical scheme similar to Judd-Offelt's theory is carried out for the observed 4f-4f transitions. It is shown that the theory may be used successfully for the quantitative description of magnetic circular dichroism (MCD) spectra (and Faraday effect spectra) in rare-earth paramagnetic glasses.