The principal discovery of Prykhotko was published in her 1944 paper based on the experimental data collected still in Kharkov, and in her 1948 follow-up paper. She reported the discovery in the absorption spectra of monocrystals of naphthalene two new bands that were polarized along the symmetry axes of the crystal, as distinct from the majority of bands that there present in both components of the spectrum at the same frequencies. Because individual molecules in crystalline naphthalene are tilted with respect to the crystal axes, existence of strongly polarized absorption bands proved unambiguously that electronic excitation is not localized at individual molecules but propagates across the crystal. Prykhotko's discovery stimulated development of Davydov' theory of molecular excitons for crystals including several molecules in a unit cell. While existence of excitons was predicted by
Yakov Frenkel and afterwards by
Gregory Wannier and
Nevill Francis Mott, Prykhotko's was the first convincing experimental discovery of excitons. The follow-up experiments on low-temperature spectra of benzine crystals confirmed agreement between the theory and experiment. In the 1950s and 1960s Prykhotko and her group carried out systematic optical studies of the absorption and luminescence spectra of benzene, its homologues and other molecular crystals. They investigated polymorphic phase transitions, the influence of impurities and lattice defects on exciton luminescence, and developed high-precision methods for measuring absorption and dispersion of light in molecular crystals. The results revealed a number of new regularities in the interaction of light with molecular crystals and became reference data for later work in crystal optics. In her later years Prykhotko supervised detailed studies of the absorption spectra of antiferromagnetic solid α-oxygen in strong magnetic fields at temperatures close to 1 K. This work demonstrated the existence of biexcitons and exciton–magnon coupling in molecular crystals and is regarded as a significant contribution to the spectroscopy of antiferromagnetic states. Under her direction the Institute of Physics of the Academy of Sciences of the Ukrainian SSR became a major centre for the design of cryogenic equipment. Her group developed robust metal optical cryostats that replaced fragile glass Dewar vessels and were widely adopted in low-temperature spectroscopy laboratories in the USSR. == Works ==