Authors: Tsuneo Hirano
Source: Journal of Computer Chemistry Japan -International Edition (article, 2022-01-01)
Field: Chemistry — Physical and Theoretical Chemistry

Computer Chemistry: Then and Now In 1929, Dirac wrote [1] "The general theory of quantum mechanics is now almost complete, … The underlying physical laws necessary for the mathematical theory of a large part of physics and the whole of chemistry are thus completely known, and the difficulty is only that the exact application of these laws leads to equations much too complicated to be soluble.It therefore becomes desirable that approximate practical methods of applying quantum mechanics should be developed, … " Today, in 2022, the last statement in this quotation has been fulfilled not only by "approximate practical methods" but also quite accurate first-principle quantum mechanical methods with the help of the (electric) computer.We can predict and understand, for example, the rotational and vibrational properties of a molecule with a precision comparable to the experimental laser-based molecular spectroscopy, the 7-or 8-digits accuracy of which is based on Laser technology.When this author tried to understand the in situ ESR spectrum observed in the radical polymerization with AIBN/Al(C 2 H 5 ) 3 initiator system in 1967, we elucidated the spectrum using a hand-cranked calculator in Hückel molecular orbital framework [2].Theoretical chemistry at that time and before then was carried out using "paper and pencil" with a hand-cranked calculator at best: for example, Octet theory by Lewis, Hard and Soft Acids and Bases theory by Pearson, HOMO-LUMO frontier orbital theory by the Fukui, Yonezawa, Nagata, Shingu group, and so on.However, a computer is now indispensable for the understanding of the chemistry of molecules and matter and also for the treatment of chemical information and its AI application.Our society evolved in 2002 from two societies, one, from the Japan Chemistry Program Exchange (JCPE) for computational chemistry, and the other, the Chemical Software Society of Japan (CSSJ) for chemical software.Although there were a few journals for computational chemistry at the time, there was no journal, even now, covering the area of "Computer and Chemistry" and "Computer Chemistry."So, we founded a Japanese language journal of our society, Journal of Computer Chemistry, Japan (JCCJ) in 2002.In addition to JCCJ, in 2015 we founded an English language journal, Journal of Computer Chemistry, Japan -International Edition (JCCJIE), also for a new field characterized by two keywords "Computer" and "Chemistry."This journal is open to people engaging in any field characterized by these two keywords, including theoretical or computational chemistry, studies of matter and materials, studies of bio-related problems, chemical information such as cheminformatics and structure-activity relationship, data-driven AI, and even algorithm in computer operation such as full-utilization of CPUs in parallel computation.In the first year, the number of contributed papers was 4, increasing steadily.We hope this unique Journal will contribute to the fruitful progress of science and technology related to Computer Chemistry today and in the future. Chemistry ; Computer science Various Chemistry Research Topics