Evolution of DFT studies in view of a scientometric perspective

Abstract

Background: This bibliometric study aims to analyze the publications in which density functional theory (DFT) plays a major role. The bibliometric analysis is performed on the full publication volume of 114,138 publications as well as sub-sets defined in terms of six different types of compounds and nine different research topics. Also, a compound analysis is presented that shows how many compounds with specific elements are known to be calculated with DFT. This analysis is done for each element from hydrogen to nobelium.

Results: We find that hydrogen, carbon, nitrogen, and oxygen occur most often in compounds calculated with DFT in terms of absolute numbers, but a relative perspective shows that DFT calculations were performed rather often in comparison with experiments for rare gas elements, many actinides, some transition metals, and polonium.

Conclusions: The annual publication volume of DFT literature continues to grow steadily. The number of publications doubles approximately every 5-6 years while a doubling of publication volume every 11 years is observed for the CAplus database (14 years if patents are excluded). Calculations of the structure and energy of compounds dominate the DFT literature.

Keywords: Chemical bibliometrics; Compound bibliometrics; DFT; Publication analysis; RPYS.

Fig. 1

Overall annual volume of DFT publications since 1980

Fig. 2

Growth of DFT publications in terms of research topics since 1980. These research topics comprise 98,357 documents. The curve for all DFT publications is included for comparison

Fig. 3

Periodic table shown as a heat map containing the number of compounds mentioned within our publication set of DFT literature (DFT-related publications). The cells are color-coded: from red (very high occurrence) over orange and yellow to green (very low occurrence)

Fig. 4

Percentage of compounds with DFT-related publications relative to all compounds registered at CAS. The cells are color-coded: from red (very high occurrence) over orange and yellow to green (very low occurrence)

Fig. 5

Percentage of compounds with DFT-related publications relative to all DFT-related compounds (n = 558.619). The cells are color-coded: from red (very high occurrence) over orange and yellow to green (very low occurrence)

Fig. 6

Annual publication volume in terms of DFT studies that investigate compounds containing certain elements centered on carbon-containing compounds

Fig. 7

Annual publication volume in terms of DFT studies that investigate specific compound groups

Fig. 8

Annual distribution of the references cited in DFT publications across their reference publication years within the time period 1950-1990. Only references with a minimum reference count of 100 are considered here