Chirantan Pramanik

About Me

I am an isotope geochemist working on stable isotope fractionation in carbonate minerals using density functional theory (DFT), ab initio molecular dynamics (AIMD), and geochemical archive datasets. My research focuses on stable Mg, S, Ca, O, C and clumped isotope systems, carbonate-associated sulfate, impurity effects in minerals, and the geochemical applications of isotope proxies in environmental and sedimentary systems.

Research Interests

Current Research

Impurity Effects on Isotope Fractionation in Calcite and Aragonite

Natural carbonate minerals rarely form as chemically pure phases. This project investigates how magnesium, sulfate and other lattice impurities modify the local bonding environment of calcite and aragonite and alter equilibrium isotope fractionation factors. Using density functional theory and lattice-dynamics calculations, I quantify the influence of impurity concentration on Mg, S, Ca, O, C and clumped isotope systematics in carbonate minerals.

Equilibrium Isotope Fractionation from First-Principle Calculations

This research develops theoretical frameworks for calculating equilibrium isotope fractionation factors using density functional theory, vibrational spectroscopy and reduced partition function ratios. Applications include carbonate minerals, aqueous species, sulfates, silicates and mineral-fluid systems relevant to environmental and geological processes.

Carbonate-Associated Sulfate (CAS)

Carbonate-associated sulfate preserves valuable information about the sulfur cycle, seawater chemistry and diagenetic alteration. My work explores the structural incorporation of sulfate into carbonate minerals and the controls on sulfur and oxygen isotope fractionation between CAS and aqueous sulfate through a combination of quantum mechanical calculations and geochemical modeling.

Mg and Ca Isotope Systematics in Carbonates and Diagenesis

Magnesium and calcium isotopes provide important constraints on carbonate precipitation, recrystallization, dolomitization and fluid–rock interaction. This project investigates equilibrium and kinetic controls on Mg and Ca isotope fractionation and their applications to reconstructing seawater chemistry, sedimentary diagenesis and global biogeochemical cycles.

Carbonate Clumped-Isotope Reordering

Clumped-isotope signatures in carbonates are widely used as temperature proxies, but they can be modified during burial and diagenesis. My research combines first-principles calculations, reaction-pathway modeling and isotope thermodynamics to understand the mechanisms and rates of clumped-isotope reordering and their implications for paleoclimate reconstructions.

Selected Publications

Pramanik, C., and Halevy, I. (2026). First-principle study of mineral-solution equilibrium isotope fractionations of magnesium, sulfate and calcium in CaCO₃. Geochimica et Cosmochimica Acta, xxx, xx–xx.

Mondal, R., Pramanik, C., Chatterjee, S., Ghosh, P., and Saha-Dasgupta, T. (2025). Lithium isotopic fractionation in olivine crystal in presence of iron at variable temperatures: A first-principles study. Geochimica et Cosmochimica Acta, 391, 144–157.

Pramanik, C., Chatterjee, S., Fosu, B.R., and Ghosh, P. (2020). Isotopic fractionation during acid digestion of calcite: a combined ab initio quantum chemical simulation and experimental study. Rapid Communications in Mass Spectrometry, e8790.

Pramanik, C., Ghosh, P., Banerjee, S., and Liang, M.C. (2020). Ab initio quantum chemical studies of isotopic fractionation during acid digestion reaction of dolomite for clumped isotope application. Rapid Communications in Mass Spectrometry, e8926.

Banerjee, S., Ghosh, P., Pramanik, C., and Reddy, B.S. Fractionation of stable oxygen and clumped isotope during acid digestion of calcite in the presence of an external DC electric field. Rapid Communications in Mass Spectrometry (2020).