88 citations · 388 across the 27 of their papers we have counts for
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Effect of Nano-Confinement on NMR Relaxation of Heptane in Kerogen from MD Simulations and Measurements
Arjun Valiya Parambathu, Walter G. Chapman, George J. Hirasaki +2
Kerogen-rich shale reservoirs will play a key role during the energy transition, yet the effects of nano-confinement on the NMR relaxation of hydrocarbons in kerogen are poorly und…
Molecular dynamics simulations of H NMR relaxation in Gd--aqua
Philip M. Singer, Arjun Valiya Parambathu, Thiago J. Pinheiro dos Santos +5
Atomistic molecular dynamics simulations are used to investigate H NMR relaxation of water from paramagnetic Gd ions in solution at 25C. Simulations of t…
H-NMR Dipole-Dipole Relaxation in Fluids: Relaxation of Individual H-H Pairs versus Relaxation of Molecular Modes
D. Asthagiri, Walter G. Chapman, George J. Hirasaki +1
The intra-molecular H-NMR dipole-dipole relaxation of molecular fluids has traditionally been interpreted within the Bloembergen-Purcell-Pound (BPP) theory of NMR intra-molecul…
Elucidating the H NMR relaxation mechanism in polydisperse polymers and bitumen using measurements, MD simulations, and models
Philip M. Singer, Arjun Valiya Parambathu, Xinglin Wang +4
The mechanism behind the H NMR frequency dependence of and the viscosity dependence of for polydisperse polymers and bitumen remains elusive. We elucidate the matte…
Molecular Dynamics Simulations of NMR Relaxation and Diffusion of Heptane Confined in a Polymer Matrix
Arjun Valiya Parambathu, Philip M. Singer, George J. Hirasaki +2
The mechanism behind the NMR surface relaxation and the large / ratio of light hydrocarbons confined in the nano-pores of kerogen remains poorly understood, and consequen…
An Efficient Algorithm for Interfacial Statistical Associating Fluid (iSAFT) in Cylindrical Geometry
Shun Xi, Jinlu Liu, Arjun Valiya Parambathu +2
In this work we present an efficient numerical algorithm for the solution of interfacial statistical associating fluid theory (iSAFT) in cylindrical geometry to facilitate the stud…
NMR Spin-Rotation Relaxation and Diffusion of Methane
Philip M. Singer, D. Asthagiri, Walter G. Chapman +1
The translational-diffusion coefficient and the spin-rotation contribution to the H NMR relaxation time for methane (CH) are investigated using MD (molecular…
Role of Internal Motions and Molecular Geometry on the NMR Relaxation of Hydrocarbons
Philip M. Singer, Dilip Asthagiri, Zeliang Chen +3
The role of internal motions and molecular geometry on H NMR relaxation times in hydrocarbons is investigated using MD (molecular dynamics) simulations of the autocor…
Electrostatic and induction effects in the solubility of water in alkanes
D. Asthagiri, A. Valiya Parambathu, Deepti Ballal +1
Experiments show that at 298~K and 1 atm pressure the transfer free energy, , of water from its vapor to liquid normal alkanes () is negative…
Molecular Dynamics Simulations of NMR Relaxation and Diffusion of Bulk Hydrocarbons and Water
P. M. Singer, D. Asthagiri, W. G. Chapman +1
Molecular dynamics (MD) simulations are used to investigate H nuclear magnetic resonance (NMR) relaxation and diffusion of bulk -CH to -CH hydroc…
Stabilized density gradient theory algorithm for modeling interfacial properties of pure and mixed systems
Xiaoqun Mu, Florian Frank, Faruk O. Alpak +1
Density gradient theory (DGT) allows fast and accurate determination of surface tension and density profile through a phase interface. Several algorithms have been developed to app…