Clemens Roothaan

12.3k total citations · 5 hit papers
33 papers, 9.8k citations indexed

About

Clemens Roothaan is a scholar working on Atomic and Molecular Physics, and Optics, Physical and Theoretical Chemistry and Computational Theory and Mathematics. According to data from OpenAlex, Clemens Roothaan has authored 33 papers receiving a total of 9.8k indexed citations (citations by other indexed papers that have themselves been cited), including 16 papers in Atomic and Molecular Physics, and Optics, 8 papers in Physical and Theoretical Chemistry and 5 papers in Computational Theory and Mathematics. Recurrent topics in Clemens Roothaan's work include Atomic and Molecular Physics (9 papers), Advanced Chemical Physics Studies (9 papers) and Advanced Physical and Chemical Molecular Interactions (5 papers). Clemens Roothaan is often cited by papers focused on Atomic and Molecular Physics (9 papers), Advanced Chemical Physics Studies (9 papers) and Advanced Physical and Chemical Molecular Interactions (5 papers). Clemens Roothaan collaborates with scholars based in United States and Mexico. Clemens Roothaan's co-authors include W Kołos, Howard D. Cohen, A. W. Weiss, Lester M. Sachs, M. Yoshimine, E. Clementi, Jürgen Hinze, Paul S. Kelly, R. A. Sack and Arnold C. Wahl and has published in prestigious journals such as Proceedings of the National Academy of Sciences, The Journal of Chemical Physics and Reviews of Modern Physics.

In The Last Decade

Clemens Roothaan

31 papers receiving 9.2k citations

Hit Papers

New Developments in Molecular Orbital Theory 1951 2026 1976 2001 1951 1960 1965 1951 1960 1000 2.0k 3.0k 4.0k
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. New Developments in Molecular Orbital Theory
    1951 4.3k citations Clemens Roothaan Reviews of Modern Physics profile →
  2. Self-Consistent Field Theory for Open Shells of Electronic Systems
    1960 1.6k citations Clemens Roothaan Reviews of Modern Physics profile →
  3. Electric Dipole Polarizability of Atoms by the Hartree—Fock Method. I. Theory for Closed-Shell Systems
    1965 686 citations Howard D. Cohen, Clemens Roothaan The Journal of Chemical Physics profile →
  4. A Study of Two-Center Integrals Useful in Calculations on Molecular Structure. I
    1951 637 citations Clemens Roothaan The Journal of Chemical Physics profile →
  5. Accurate Electronic Wave Functions for theH2Molecule
    1960 573 citations Clemens Roothaan et al. Reviews of Modern Physics profile →

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Clemens Roothaan United States 20 6.9k 2.1k 2.1k 1.7k 1.6k 33 9.8k
R. McWeeny United Kingdom 41 5.4k 0.8× 1.8k 0.9× 2.1k 1.0× 1.6k 0.9× 1.9k 1.2× 93 8.3k
Per‐Olov Löwdin Sweden 38 9.2k 1.3× 1.9k 0.9× 2.5k 1.2× 1.9k 1.1× 1.1k 0.7× 115 12.1k
C. A. Coulson Slovakia 46 4.1k 0.6× 1.3k 0.6× 1.6k 0.8× 1.7k 1.0× 1.6k 1.0× 208 7.3k
Leland C. Allen United States 49 3.4k 0.5× 2.3k 1.1× 1.8k 0.9× 1.7k 1.0× 2.0k 1.2× 152 7.7k
Gerald A. Segal United States 27 3.2k 0.5× 1.9k 0.9× 1.6k 0.7× 971 0.6× 1.6k 1.0× 48 5.8k
Klaus Ruedenberg United States 55 8.4k 1.2× 2.5k 1.2× 3.6k 1.7× 2.1k 1.2× 2.7k 1.7× 196 11.9k
Delano P. Chong Canada 36 5.1k 0.7× 1.4k 0.7× 1.8k 0.9× 1.8k 1.1× 1.4k 0.8× 222 7.4k
David M. Bishop Canada 50 6.1k 0.9× 2.3k 1.1× 1.2k 0.6× 1.6k 1.0× 1.1k 0.7× 248 8.6k
J.N. Murrell United Kingdom 53 7.6k 1.1× 3.6k 1.7× 3.1k 1.5× 2.5k 1.4× 3.0k 1.9× 311 12.9k
R. K. Nesbet United States 46 6.8k 1.0× 1.6k 0.8× 1.2k 0.6× 1.1k 0.7× 700 0.4× 199 8.2k

Countries citing papers authored by Clemens Roothaan

Since Specialization
Citations

This map shows the geographic impact of Clemens Roothaan's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Clemens Roothaan with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Clemens Roothaan more than expected).

Fields of papers citing papers by Clemens Roothaan

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Clemens Roothaan. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Clemens Roothaan. The network helps show where Clemens Roothaan may publish in the future.

Co-authorship network of co-authors of Clemens Roothaan

This figure shows the co-authorship network connecting the top 25 collaborators of Clemens Roothaan. A scholar is included among the top collaborators of Clemens Roothaan based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Clemens Roothaan. Clemens Roothaan is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Roothaan, Clemens, John Detrich, & Darrel G. Hopper. (2009). An improved MCSCF method. International Journal of Quantum Chemistry. 16(S13). 93–101. 8 indexed citations
2.
Roothaan, Clemens. (1998). Remembering Włodek Kołos. Polish Journal of Chemistry. 72. 1288–1289.
3.
Roothaan, Clemens, et al.. (1997). Calculation of 3n-j symbols by Labarthe's method. International Journal of Quantum Chemistry. 63(1). 57–64. 7 indexed citations
4.
Roothaan, Clemens. (1991). My life as a physicist: memories and perspectives. Journal of Molecular Structure THEOCHEM. 234. 1–12. 2 indexed citations
5.
Roothaan, Clemens. (1990). The General MCSCF Method with Full Symmetry Reduction. Australian Journal of Physics. 43(5). 439–442. 2 indexed citations
6.
Roothaan, Clemens & John Detrich. (1983). General quadratically convergent multiconfiguration self-consistent-field theory in terms of reduced matrix elements. Physical review. A, General physics. 27(1). 29–56. 7 indexed citations
7.
Roothaan, Clemens, et al.. (1978). Visualization of electron correlation in ground states of He and H−. Chemical Physics Letters. 58(3). 321–325. 28 indexed citations
8.
Bagus, P. S., T. L. Gilbert, & Clemens Roothaan. (1972). Hartree-Fock Wavefunctions of Nominal Accuracy for He through Rb+ Calculated by the Expansion Method. The Journal of Chemical Physics. 56(10). 5195–5196. 94 indexed citations
9.
Hinze, Jürgen & Clemens Roothaan. (1967). Multi-Configuration Self-Consistent-Field Theory. Progress of Theoretical Physics Supplement. 40. 37–51. 143 indexed citations
10.
Roothaan, Clemens, et al.. (1966). Accurate Analytical Self-Consistent-Field Functions for Atoms. VIII. The Ground States ofK+, K, and Ca. Physical Review. 141(1). 174–175. 13 indexed citations
11.
Cohen, Howard D. & Clemens Roothaan. (1965). Electric Dipole Polarizability of Atoms by the Hartree—Fock Method. I. Theory for Closed-Shell Systems. The Journal of Chemical Physics. 43(10). S34–S39. 686 indexed citations breakdown →
12.
Roothaan, Clemens & Paul S. Kelly. (1963). Accurate Analytical Self-Consistent Field Functions for Atoms. III. The1s22sm2pnStates of Nitrogen and Oxygen and Their Ions. Physical Review. 131(3). 1177–1182. 129 indexed citations
13.
Clementi, E., Clemens Roothaan, & M. Yoshimine. (1962). Accurate Analytical Self-Consistent Field Functions for Atoms. II. Lowest Configurations of the Neutral First Row Atoms. Physical Review. 127(5). 1618–1620. 260 indexed citations
14.
Roothaan, Clemens. (1960). Self-Consistent Field Theory for Open Shells of Electronic Systems. Reviews of Modern Physics. 32(2). 179–185. 1576 indexed citations breakdown →
15.
Roothaan, Clemens & A. W. Weiss. (1960). Correlated Orbitals for the Ground State of Heliumlike Systems. Reviews of Modern Physics. 32(2). 194–205. 217 indexed citations
16.
Mulliken, Robert S. & Clemens Roothaan. (1959). BROKEN BOTTLENECKS AND THE FUTURE OF MOLECULAR QUANTUM MECHANICS. Proceedings of the National Academy of Sciences. 45(3). 394–398. 32 indexed citations
17.
Ruedenberg, Klaus, et al.. (1956). Study of Two-Center Integrals Useful in Calculations on Molecular Structure. III. A Unified Treatment of the Hybrid, Coulomb, and One-Electron Integrals. The Journal of Chemical Physics. 24(2). 201–220. 129 indexed citations
18.
Roothaan, Clemens & Klaus Ruedenberg. (1954). Errata: A Study of Two-Center Integrals Useful in Calculations on Molecular Structure. I, II. The Journal of Chemical Physics. 22(4). 765–765. 15 indexed citations
19.
Roothaan, Clemens. (1951). New Developments in Molecular Orbital Theory. Reviews of Modern Physics. 23(2). 69–89. 4263 indexed citations breakdown →
20.
Roothaan, Clemens. (1951). A Study of Two-Center Integrals Useful in Calculations on Molecular Structure. I. The Journal of Chemical Physics. 19(12). 1445–1458. 637 indexed citations breakdown →

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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