This paper continues a generalization of our observations on the improvement of properties from semiconductor GaP:N single crystals grown over 40 years ago and their convergence to the behavior of the GaP nanoparticles prepared recently in framework of the mentioned below current US/Moldova project. Throughout the decades these crystals have been used investigate the electro- and photo-luminescence, photoconductivity, bound excitons, non-linear optics and other phenomena. Their long-term ordering has been observed as an interesting accompanying process, which can only be studied in this unusual situation when a researcher has a unique set of samples and the persistence to observe them over decade time scales. Since 2005 the influence of long-term ordering on optical and mechanical properties of GaP has been studied jointly with the US partners using measurements of photoluminescence (PL), photomechanical effect (PME), microhardness, dislocation density, Raman light scattering (RLS) and X-ray diffraction (XRD). In spite of the long-term character of the measurements, the same experimental conditions were strictly adhered. In addition, freshly prepared GaP single crystals were purchased from Sigma-Aldrich Co. for comparison with the samples from our unique collection of the long-term ordered GaP crystals. The study of freshly-prepared crystals provides a good opportunity to compare these long-term measurements obtained on the old equipment with the results obtained from newly freshly grown crystals. We demonstrate that the long-term natural stimuli improving perfection of our crystals prevail over the other processes and this feature could lead to novel heterogeneous systems and new semiconductor devices with high temporal stability. We show that diffusion and stress relaxation over time lead to the host atoms migrating to their proper equilibrium positions and a uniform redistribution of impurities is formed. Along with the long-term ordering, the essential role of the photomechanical effect in the formation of close to ideal crystals has been observed through the investigation of microhardness, PME, RLS and XRD. We demonstrate that the highly ordered nature that develops throughout the decades facilitates enhanced stimulated emission, increases the radiative recombination efficiency and spectral range of luminescence. At room temperature in common with the GaP nanoparticles, the bulk long-term ordered single crystals having the forbidden gap around 2.2 eV develop the bright luminescence shifted to ultraviolet side up to 3 eV. For the first time, to the best of our knowledge, we observe a new type of the crystal lattice where the host atoms occupy their proper (equilibrium) positions in the crystal field, while the impurities, once periodically inserted into the lattice, divide it in the short chains of equal length, where the host atoms develop harmonic vibrations. This periodic substitution of a host atom by an impurity allows the impurity to participate in the formation of the crystal's energy bands. It leads to the change in the value of the forbidden energy gap, to the appearance of a crystalline excitonic phase, and to the broad energy bands instead of the energy levels of bound excitons. The high perfection of this new lattice leads to the abrupt decrease of non-radiative mechanisms of electron-hole recombination, to both the relevant increase of efficiency and spectral range of luminescence and to the stimulated emission of light due to its amplification inside the well arranged, defectfree medium of the crystal. Thus, our unique collection of pure and doped crystals of semiconductors grown in the 1960s provides an opportunity to observe the long term evolution of properties of the key electronic materials. This study of GaP:N brings a novel perspective to improving the quality of semiconductor crystals. The further development of techniques for the growth of thin films and bulk crystals with ordered distribution of impurities and the proper localization of host atoms inside the lattice should be a high priority. The authors are very grateful to the US Department of State, Institute of International Exchange, Washington, DC, The US Air Force Office for Scientific Research, the US Office of Naval Research Global, Civilian R&D Foundation, Arlington, VA, Science & Technology Center in Ukraine (STCU) and the US sponsors of the current STCU Project 4610 “Advanced Light Emissive Device Structures”, Clemson University, SC, University of Central Florida, FL, Istituto di elettronica dello stato solido, CNR, Rome, Italy, Universita degli studi, Cagliari, Italy, Joffe Physico-Technical Institute, St.Petersburg State Polytechnical University, Russia, Institute of Applied Physics and Academy of Sciences of Moldova for support and attention to this protracted (1963-present time) research.