Titanium dioxide (TiO₂), one of the most frequently used materials in general, has emerged as an excellent photocatalytic material for environmental applications. In this review, principles and mechanisms of the photocatalytic activity of TiO₂ have been analyzed. Structural and physical specificities of TiO₂ nanoparticles, such as morphology, crystal structure, and electronic and optical properties, have been considered in the context of photocatalytic applications. A review of the influence of several factors, such as the type and dimensions of photocatalyst particles, pH of the solution, the influence of oxidants/electron acceptors, and light intensity on photocatalytic properties of TiO₂, has been provided. Superhydrophilicity as an intrinsic property of the TiO₂ surface was discussed through surface reconstruction on TiO₂ during the reversible hydrophilic changes. Additionally, attention was paid to improving the photocatalytic properties of TiO₂ particles through aggregation and agglomeration.

We present the atomistica.online, a web application for generating input files for the ORCA molecular modelling package. atomistica.online is entirely made with the Anvil platform, which allows the development of web applications using only Python programming language. ORCA is one of the most, if not the most, powerful molecular modelling tools covering a wide range of possibilities for atomistic calculations on molecules. Speed, ease of installation and use, and clear and intuitive syntax for input files are some of ORCA's characteristics that make it one of the most cited modelling tools in the last several years. Nevertheless, although tools for generating input files for ORCA exist, they are not available as online applications. In this work, we demonstrate how the combination of Python programming language and the Anvil platform makes the development of scientific web applications available to all scientists. All tools within atomistica.online are freely available at the project's official website – https://atomistica.online