22 Jul 2026Open access
Negative σ-Holes on Fluorine in Molecules Revisited: Halogen Bonding or Counterintuitive, Anti-Electrostatic Interactions?Publisher siteInternational Journal of Molecular Sciences, Crystallography and molecular interactions
Active, last published 2026
In porphyrin metabolism and disorders
Helder M.
Marques
Scholar“Research focused on Porphyrin Metabolism and Disorders and adjacent fields.”
University of the Witwatersrand
South Africa39
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01 · About the work
What I study
elder M. Marques is a researcher working on Porphyrin Metabolism and Disorders. A fuller summary will appear once they update their profile.
02 · Reach
Publication output and reach
Helder's work has been cited 5,981 times across 2 active years. Bars show publications per year; the line shows cumulative citation totals across publications first appearing in each year.
03 · Research focus
Topics
Porphyrin Metabolism and Disorders×72Crystallography and molecular interactions×67Crystallization and Solubility Studies×63X-ray Diffraction in Crystallography×62Porphyrin and Phthalocyanine Chemistry×57
04 · Where I am
Affiliations
Affiliation on published researchUniversity of the Witwatersrand, South AfricaDrawn from the institution listed on this researcher’s published work.
Research themes (UN SDGs)
05 · Selected work
Recent publications
7 works30 Jun 2026
The chemistry of the cobalt corrinoids ― Recent advances and emerging themes. Part 1: The chemistry and industrial production of cobalt corrinoidsPublisher siteJournal of Inorganic Biochemistry, Porphyrin and Phthalocyanine Chemistry
18 Jun 2026Open access
Halogen Bonds or Not? Reassessing Noncovalent Interactions in Crystals of Periodate Anion from the Cambridge Structural DatabasePublisher siteMolecules, Crystallography and molecular interactions
10 Jun 2026Open access
Anti-Electrostatic Anion-Anion Noncovalent Interactions Are Not Halogen Bonds: Evidence from X···O Contacts in XO4− Dimers and Oligomers in Crystals StructuresPublisher siteInternational Journal of Molecular Sciences, Crystallography and molecular interactions
8 Apr 2026Open access
Molecular Electrostatic Surface Potential: A Predictive Framework for Noncovalent Interactions and Adsorption Characteristics in Molecular EntitiesPublisher siteInternational Journal of Molecular Sciences, Surface Chemistry and Catalysis
9 Sept 202413cites
π-Hole Halogen Bonds Are Sister Interactions to σ-Hole Halogen BondsPublisher siteCrystal Growth & Design, Crystallography and molecular interactions
22 Apr 20248cites
Corrins and porphyrins: two of nature’s pigments of lifePublisher siteJournal of Coordination Chemistry, Porphyrin Metabolism and Disorders
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