World's Best Scientists 2026 revealed!

D-Index & Metrics

Chemistry

D-Index
47
Citations
8977
World Ranking
15555
National Ranking
3925

Patrik R. Callis publication distribution in Chemistry in 2026

The chart shows the distribution of publications by all Research.com ranked scientists in the field of Chemistry in 2026. The highlighted bar marks where Patrik R. Callis sits on this spectrum.

61–80 publications: 66 scientists 81–100 publications: 302 scientists 101–120 publications: 623 scientists 121–140 publications: 918 scientists 141–160 publications: 1,218 scientists 161–180 publications: 1,350 scientists 181–200 publications: 1,344 scientists 201–220 publications: 1,281 scientists 221–240 publications: 1,216 scientists 241–260 publications: 1,100 scientists 261–280 publications: 979 scientists 281–300 publications: 939 scientists 301–320 publications: 764 scientists 321–340 publications: 643 scientists 341–360 publications: 628 scientists 361–380 publications: 522 scientists 381–400 publications: 459 scientists 401–420 publications: 397 scientists 421–440 publications: 327 scientists 441–460 publications: 270 scientists 461–480 publications: 265 scientists 481–500 publications: 252 scientists 501–520 publications: 201 scientists 521–540 publications: 185 scientists 541–560 publications: 148 scientists 561–580 publications: 148 scientists 581–600 publications: 132 scientists 601–620 publications: 114 scientists 621–640 publications: 104 scientists 641–660 publications: 91 scientists 661–680 publications: 92 scientists 681–700 publications: 73 scientists 701–720 publications: 57 scientists 721–740 publications: 54 scientists 741–760 publications: 67 scientists 761–780 publications: 45 scientists 781–800 publications: 46 scientists 801–820 publications: 39 scientists 821–840 publications: 32 scientists 841–860 publications: 36 scientists 861–880 publications: 29 scientists 881–900 publications: 26 scientists 901–920 publications: 24 scientists 921–940 publications: 14 scientists 941–960 publications: 23 scientists 961–980 publications: 28 scientists 981–1,000 publications: 15 scientists 1,001–1,020 publications: 29 scientists 1,021–1,040 publications: 12 scientists 1,041–1,060 publications: 19 scientists 1,061–1,080 publications: 12 scientists 1,081–1,100 publications: 6 scientists 1,101–1,120 publications: 8 scientists 1,121–1,140 publications: 12 scientists 1,141–1,160 publications: 5 scientists 1,161–1,180 publications: 6 scientists 1,181–1,200 publications: 14 scientists 1,201–1,220 publications: 7 scientists 1,221–1,240 publications: 2 scientists 1,241–1,260 publications: 6 scientists 1,261–1,280 publications: 4 scientists 1,281–1,294 publications: 6 scientists 1,295+ publications: 100 scientists
61 publications 1,295+

This scientist: 136 publications — 9th percentile

9% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 1,295 publications or more.

Patrik R. Callis D-index placement in Chemistry in 2026

The chart shows the D-index (discipline H-index) distribution of Chemistry scientists ranked by Research.com in 2026. The highlighted bar marks where Patrik R. Callis sits on this spectrum.

40–41 D-Index: 289 scientists 42–43 D-Index: 612 scientists 44–45 D-Index: 808 scientists 46–47 D-Index: 776 scientists 48–49 D-Index: 835 scientists 50–51 D-Index: 861 scientists 52–53 D-Index: 872 scientists 54–55 D-Index: 933 scientists 56–57 D-Index: 1,051 scientists 58–59 D-Index: 930 scientists 60–61 D-Index: 882 scientists 62–63 D-Index: 834 scientists 64–65 D-Index: 731 scientists 66–67 D-Index: 775 scientists 68–69 D-Index: 683 scientists 70–71 D-Index: 646 scientists 72–73 D-Index: 561 scientists 74–75 D-Index: 501 scientists 76–77 D-Index: 437 scientists 78–79 D-Index: 388 scientists 80–81 D-Index: 354 scientists 82–83 D-Index: 292 scientists 84–85 D-Index: 275 scientists 86–87 D-Index: 254 scientists 88–89 D-Index: 235 scientists 90–91 D-Index: 185 scientists 92–93 D-Index: 192 scientists 94–95 D-Index: 155 scientists 96–97 D-Index: 163 scientists 98–99 D-Index: 125 scientists 100–101 D-Index: 105 scientists 102–103 D-Index: 105 scientists 104–105 D-Index: 112 scientists 106–107 D-Index: 88 scientists 108–109 D-Index: 68 scientists 110–111 D-Index: 69 scientists 112–113 D-Index: 65 scientists 114–115 D-Index: 79 scientists 116–117 D-Index: 61 scientists 118–119 D-Index: 44 scientists 120–121 D-Index: 37 scientists 122–123 D-Index: 40 scientists 124–125 D-Index: 33 scientists 126–127 D-Index: 26 scientists 128–129 D-Index: 34 scientists 130–131 D-Index: 35 scientists 132–133 D-Index: 25 scientists 134–135 D-Index: 27 scientists 136–137 D-Index: 17 scientists 138–139 D-Index: 16 scientists 140–141 D-Index: 20 scientists 142–143 D-Index: 20 scientists 144–145 D-Index: 15 scientists 146–147 D-Index: 9 scientists 148–149 D-Index: 9 scientists 150–151 D-Index: 16 scientists 152–153 D-Index: 11 scientists 154–155 D-Index: 9 scientists 156–157 D-Index: 3 scientists 158 D-Index: 3 scientists 159+ D-Index: 98 scientists
40 D-Index 159+

This scientist: 47 D-Index — 14th percentile

14% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 159 D-Index or more.

Overview

Patrik R. Callis is affiliated with Montana State University in the United States. Their research primarily falls within the field of Biochemistry, Genetics and Molecular Biology, including subfields such as Molecular Biology, Biophysics, Cellular and Molecular Neuroscience, Atomic and Molecular Physics and Optics, and Physical and Theoretical Chemistry.

The scientist's work focuses on topics including Protein Structure and Dynamics, Advanced Fluorescence Microscopy Techniques, Photoreceptor and Optogenetics Research, Receptor Mechanisms and Signaling, Spectroscopy and Quantum Chemical Studies, Photochemistry and Electron Transfer Studies, and Electrochemical Analysis and Applications.

Patrik R. Callis has published multiple research papers in various scientific journals. Some of the notable recent papers include:

  • Local Electric Field Controls Fluorescence Quantum Yield of Red and Far-Red Fluorescent Proteins, 2021, Frontiers in Molecular Biosciences
  • Buried Liquid Interfaces as a Form of Chemistry in Confinement: The Case of 4-Dimethylaminobenzonitrile at the Silica-Aqueous Interface, 2020, Journal of the American Chemical Society
  • Water as an Essential Cofactor for All Enzymes, 2020, Biophysical Journal
  • Water as a reactant in the first step of triosephosphate isomerase catalysis, 2021, bioRxiv (Cold Spring Harbor Laboratory)
  • Surveying Enzyme Crystal Structures Reveals the Commonality of Active-Site Solvent Accessibility and Enzymatic Water Networks, 2025, ACS Omega

The publication venues where Patrik R. Callis frequently contributes include:

  • Frontiers in Molecular Biosciences
  • Journal of the American Chemical Society
  • Biophysical Journal
  • bioRxiv (Cold Spring Harbor Laboratory)
  • ACS Omega

The scientist collaborates regularly with several researchers, with frequent co-authors including Pedro L. Muíño, Mikhail Drobizhev, Rosana S. Molina, J. Nathan Scott, and Gerard G. Lambert.

Best Publications

  • Mechanisms of Tryptophan Fluorescence Shifts in Proteins

    James T. Vivian;Patrik R. Callis

  • Fluorometric determination of the neutral lipid content of microalgal cells using Nile Red

    Keith E. Cooksey;James B. Guckert;Scott A. Williams;Patrik R. Callis

  • 1LA AND 1LB TRANSITIONS OF TRYPTOPHAN : APPLICATIONS OF THEORY AND EXPERIMENTAL OBSERVATIONS TO FLUORESCENCE OF PROTEINS

    Patrik R. Callis

  • TRYPTOPHAN FLUORESCENCE SHIFTS IN PROTEINS FROM HYBRID SIMULATIONS: AN ELECTROSTATIC APPROACH

    Patrik R. Callis;Berit K. Burgess

  • Photophysics of indole derivatives : experimental resolution of La and Lb transitions and comparison with theory

    Maurice R. Eftink;LeRoy A. Selvidge;Patrik R. Callis;Aden A. Rehms

  • Advances in calculating Raman excitation profiles by means of the transform theory

    B. R. Stallard;P. M. Champion;Patrik R. Callis;A. C. Albrecht

  • Hybrid simulations of solvation effects on electronic spectra: Indoles in water

    Pedro L. Muiño;Patrik R. Callis

  • Perturbation selection rules for multiphoton electronic spectroscopy of neutral alternant hydrocarbonsa)

    Patrik R. Callis;Thomas W. Scott;A. C. Albrecht

  • Understanding the variable fluorescence quantum yield of tryptophan in proteins using QM-MM simulations. Quenching by charge transfer to the peptide backbone

    Patrik R. Callis;James T. Vivian

  • Mechanism of the Very Efficient Quenching of Tryptophan Fluorescence in Human γD- and γS-Crystallins: The γ-Crystallin Fold May Have Evolved To Protect Tryptophan Residues from Ultraviolet Photodamage†

    Jiejin Chen;Patrik R. Callis;Jonathan King

  • Mechanism of the Highly Efficient Quenching of Tryptophan Fluorescence in Human γD-Crystallin†

    Jiejin Chen;Shannon L Flaugh;Patrik R Callis;Jonathan King

  • Molecular orbital theory of the 1<i>L</i> <i>b</i> and 1<i>L</i> <i>a</i> states of indole

    Unknown

  • Two-photon-induced fluorescence.

    Patrik R. Callis

  • Molecular Orbital Theory of the 1La and 1Lb States of Indole. 2. An ab Initio Study

    Lee S. Slater;Patrik R. Callis

  • Application of the transform theory to resonance Raman excitation profiles in the Soret region of cytochrome‐c

    B. R. Stallard;P. R. Callis;P. M. Champion;A. C. Albrecht

  • AB INITIO CALCULATIONS OF VIBRONIC SPECTRA FOR INDOLE

    Patrik R. Callis;James T. Vivian;Lee S. Slater

  • Two-photon fluorescence excitation spectra of aromatic amino acids

    Aden A. Rehms;Patrik R. Callis

  • FLUORESCENT TAUTOMERS AND THE APPARENT PHOTOPHYSICS OF ADENINE AND GUANINE

    Robert W. Wilson;Patrik R. Callis

  • Resolution of La and Lb bands in methyl indoles by two-photon spectroscopy

    Aden A. Rehms;Patrik R. Callis

  • Ionization Potentials of Fluoroindoles and the Origin of Nonexponential Tryptophan Fluorescence Decay in Proteins

    TQ Liu;PR Callis;BH Hesp;M de Groot

  • Fluorescence lifetime measurements of fluoranthene, 1-naphthol, and napropamide in the presence of dissolved humic Acid.

    Shaojin. Chen;William P. Inskeep;Scott A. Williams;Patrik R. Callis

  • Fluorescence of reduced nicotinamides using one- and two-photon excitation.

    Borys Kierdaszuk;Borys Kierdaszuk;Henryk Malak;Ignacy Gryczynski;Patrik Callis

Frequent Co-Authors

Bruce S. Hudson
Bruce S. Hudson Syracuse University
Joseph R. Lakowicz
Joseph R. Lakowicz University of Maryland, Baltimore
Robert J. Twieg
Robert J. Twieg Kent State University
Bern Kohler
Bern Kohler The Ohio State University
Ignacy Gryczynski
Ignacy Gryczynski University of North Texas Health Science Center
Robert W. Woody
Robert W. Woody Colorado State University
William P. Inskeep
William P. Inskeep Montana State University
W. E. Moerner
W. E. Moerner Stanford University
Angela M. Gronenborn
Angela M. Gronenborn University of Pittsburgh

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