ИСТИНА

We obtained the temperature dependence of the equilibrium concentration of guanylurea(1+) hydrogen phosphite in water solutions. The change of density in water solutions of GUHP with a change in their concentration was investigated. The results obtained allowed the growth of GUHP crystals in various temperature and hydrodynamic mode. The effect of the pH of the solutions on the habit of the grown crystals was studied. It was revealed that with a decrease in the acidity of the initial solution to pH = 4.6 (pHinit = 3.6), a relative decrease in the growth rate of the face (010) is observed. With an increase in acidity to pH = 2.6, no change in the ratio of the growth rates of the faces of the GUHP crystal was observed. The crystal structure was refined and the nonlinear properties of the second order of the growning crystals were investigated. Absorption and generation spectra of the obtained single-crystal samples in the visible and near-IR range were also obtained.