DSc on Chemical Sciences, Professor, Chief researcher of the Laboratory of Geochemistry of the Institute of Geology of ore deposits, Petrography, Mineralogy and Geochemistry of the Russian Academy of Sciences (IGEM RAS), Professor of the Department of Chemistry of the Sergo Ordzhonikidze Russian State University for Geological Prospecting.

ORCID: 0000-0001-6049-3159
ScopusID: 55972027800
ResercherID: O-8703-2015
AuthorID: 62265
SPIN: 7708-1651

Education.
Graduated on MSc Degree in Physics from Lomonosov Moscow state University, Department of Physics, 1974. In 1981, he defended his thesis for PhD degree at the Institute of Chemical Physics of the USSR Academy of Sciences. Topic: "Kinetics of n2f4 dissociation induced by CO2 laser radiation". In 1995, he defended his thesis for DSc degree at Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences. Topic: "Physical and chemical bases of hydrothermal systems modeling".

Scientific career
1968–1974 – Diploma in physics, Department of physics, Lomonosov Moscow state University. Thesis topic "BCl3 Dissociation initiated by the radiation of a chemical HF laser".
1974–1981 – Junior Research associate of the Russian State Research Institute of Chemistry and Technology of Organoelement Compounds. Research in the field of laser chemistry.
1981– PhD thesis at the Institute of Chemical Physics of the USSR Academy of Sciences of the Topic: "Dissociation of N2F4 initiated by radiation of pulsed CO2 laser".
1982–1986 – Senior Researcher of Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences.
1986–1994 – Associate Professor of the Department of chemistry MGRI – Sergo Ordzhonikidze Russian State University for Geological Prospecting.
1994–2001 – Head of the Department of chemistry of MGRI – Sergo Ordzhonikidze Russian State University for Geological Prospecting.
1995– Chemical Sciences DSc-thesis at Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences. Dissertation topic on "Physical and chemical bases of hydrothermal systems modeling".
1996 – Professor of the Department of chemistry MGRI – Sergo Ordzhonikidze Russian State University for Geological Prospecting.
2001–2002 – Visiting Professor at the Institute of Earth Sciences (Department of Mineralogy and petrography), University of Leoben (Austria). 2008 – Fulbright scholar at the State University of Pennsylvania (USA).
2002–2003, 2016 – Visiting Professor at the Department of Geology, University of Bern.
2003 – Present – Leading Researcher (2003–2014), then Chief Researcher at Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences, Professor of the Department of Chemistry at MGRI – Sergo Ordzhonikidze Russian State University for Geological Prospecting.

Professional interests
Geochemistry, in particular the theoretical basis for describing water / rock interactions and element transport in hydrothermal fluids. Thermodynamic description of mineral/fluid equilibria in a wide range of temperatures (0–1000°C) and pressures (1–10000 bar). Obtaining thermodynamic data from experimental data. Description of processes in mixed fluids. Physical and chemical properties and description of processes in low-density water fluids. Creating new equations of state. Computer simulation of transport and deposition of ore elements under hydrothermal conditions. Development of new software for calculating equilibria in multisystem.

Main research results

• A “GeoChEq” software package has been developed for calculating equilibria in multicomponent heterogeneous hydrothermal systems in a wide range of temperatures (0-1000°C) and pressures (1–10000 bar).
• An equation of state is proposed for the thermodynamic description of neutral molecules in an aqueous solution in a wide range of state parameters (0–1000°C, 1–10000 bar) including both the near-critical region of H2O and the region of low-density water fluids.
• A new method for calculating equilibria in mixed multicomponent systems of H2O–nonpolar gas at elevated temperatures and pressures is proposed. The method is based on the consideration of electrostatic interactions between the dissolved component and surrounding solvent molecules (H2O).
• A description of the processes of 1:1 Association of electrolytes is proposed, which does not require individual adjustment parameters. The model allows calculating any thermodynamic properties of an ion pair over a wide range of pressures and temperatures, including the supercritical region.
• Based on the available experimental data, the thermodynamic properties of the water components of the Au-Ag-Cu-As-Sb-S-Se-Cl-O-h system were coordinated. The resulting thermodynamic summary makes it possible to model the transport and deposition of water components of the system over the entire range of temperatures and pressures characteristic of the hydrothermal process.

Scientific project Projects within the European Associated Laboratory LEAGE "Geochemistry of the environment":

• RFBR 05-05-66811-NCNIL "Behavior of ore elements in hydrothermal fluids of various densities: experiment and thermodynamic description"(2006–2008) – Head;
• RFBR 07-05-72553- NCNIL " Acid-base and redox properties of hydrothermal fluids in equilibrium with the most important natural ore associations in the Cu-Fe-Au-As-S-O-H system at 300–450°C and 100-1000 bar: direct experimental measurements and thermodynamic analysis "(2007–2009) – Performer;
• RFBR 06-05-64503-a "Thermodynamic description of selenide and telluride water complexes of Cu-Au-Ag metals and their role in the formation of gold deposits" (2006–2008) – Head.

Main publication:

• Prokofiev V.Y., Banks D.A., Lobanov K.V., Selektor S. L., Milichko V. A., Akinfiev N. N., Borovikov A. A., Lüders V., Chicherov M. V. Exceptional Concentrations of Gold Nanoparticles in 1.7 Ga Fluid Inclusions from the Kola Superdeep Borehole, Northwest Russia // Scientific Reports. 2020. Vol. 10(1). pp. 1108. https://doi.org/10.1038/s41598-020-58020-8.
• Akinfiev N.N., Korzhinskaya V.S., Kotova N.P., Redkin A.F., Zotov A.V. Niobium and tantalum in hydrothermal fluids: Thermodynamic description of hydroxide and hydroxofluoride complexes // Geochimica et Cosmochimica Acta. 2020. Vol. 280. pp. 102–115. https://doi.org/10.1016/j.gca.2020.04.009.
• Aranovich L., Akinfiev N. N., Golunova M. Quartz solubility in sodium carbonate solutions at high pressure and temperature // Chemical Geology. 2020. Vol. 550. 119699. DOI: 10.1016/j.chemgeo.2020.119699.
• Tagirov B.R., Filimonova O.N., Trigub A.L., Akinfiev N.N., Nickolsky M.S., Kvasnina K.O., Chareev D.F., Zotov A.V. Platinum transport in chloride-bearing fluids and melts: Insights from in situ X-ray absorption spectroscopy and thermodynamic modeling // Geochimica et Cosmochimica Acta. 2019. Vol. 254. pp. 86–101 (https://doi.org/10.1016/j.gca.2019.03.023).
• Kokh M.A., Akinfiev N.N., Pokrovski G.S., Salvi S., Guillaume D. The role of carbon dioxide in the transport and fractionation of metals by geological fluids // Geochimica et Cosmochimica Acta. 2017. Vol. 197. pp. 433–466. (http://dx.doi.org/10.1016/j.gca.2016.11.007).
• Yudovskaya M.A., Distler V.V., Prokofiev V.Yu., Akinfiev N.N. Gold mineralisation and orogenic metamorphism in the Lena province of Siberia as assessed from Chertovo Koryto and Sukhoi Log deposits // Geoscience Frontiers. 2016. No. 7. pp. 453–481. (http://dx.doi.org/10.1016/j.gsf.2015.07.010).
• Akinfiev N.N., Majer V., Shvarov Yu.V. Thermodynamic description of H2S-H2O-NaCl solutions at temperatures to 573 K and pressures to 40 MPa // Chem. Geol. 2016. Vol. 424. pp. 1–11. (http://dx.doi.org/10.1016/j.chemgeo.2016.01.006).
• Akinfiev N.N., Zotov A.V. Solubility of chlorargyrite (AgCl(cr./l.)) in water: New experimental data and a predictive model valid for a wide range of temperatures (273–873 K) and water densities (0.01–1 g•cm−3) // Geochimica et Cosmochimica Acta. 2016. Vol. 178. pp. 178–194. DOI: 10.1016/j.gca.2016.01.027.
• Akinfiev N.N., Plyasunov A.V., Pokrovski G.S. An equation of state for predicting the thermodynamic properties and vapour–liquid partitioning of aqueous Ge(OH)4 in a wide range of water densities // Fluid Phase Equilibria. 2015. Vol. 392. pp. 74–83. DOI:10.1016/j.fluid.2015.02.010.

Other professional activities

• Chairman of the Working Group "Thermodynamics of natural ore-forming fluids" of The international Association for the Genesis of Ore Deposits (IAGOD).
• Head of the Department of Chemistry of Russian State Geological Prospecting University.

Address:
Institute of Geology of ore deposits, Petrography, Mineralogy and Geochemistry of the Russian Academy of Sciences (IGEM RAS).
35, Staromonetny lane, Moscow, 119017, Russia, Phone: +7 (499) 230-82-31. e-mail: akinfiev@igem.ru, akinfievnn@mgri.ru