title: Observation of Binding and Rotation of Methane and Hydrogen within a Functional Metal-Organic Framework.
abstract: The key requirement for a portable store of natural gas is to maximize the amount of gas within the smallest possible space. The packing of methane (CH4) in a given storage medium at the highest possible density is, therefore, a highly desirable but challenging target. We report a microporous hydroxyl-decorated material, MFM-300(In) (MFM = Manchester Framework Material, replacing the NOTT designation), which displays a high volumetric uptake of 202 v/v at 298 K and 35 bar for CH4 and 488 v/v at 77 K and 20 bar for H2. Direct observation and quantification of the location, binding, and rotational modes of adsorbed CH4 and H2 molecules within this host have been achieved, using neutron diffraction and inelastic neutron scattering experiments, coupled with density functional theory (DFT) modeling. These complementary techniques reveal a very efficient packing of H2 and CH4 molecules within MFM-300(In), reminiscent of the condensed gas in pure component crystalline solids. We also report here, for the first time, the experimental observation of a direct binding interaction between adsorbed CH4 molecules and the hydroxyl groups within the pore of a material. This is different from the arrangement found in CH4/water clathrates, the CH4 store of nature.
authors.affiliation: School of Chemistry, University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom.
authors.forename: Mathew
authors.initials: M
authors.lastname: Savage
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory , Chilton, Oxfordshire OX11 0QX, United Kingdom.
authors.forename: Ivan
authors.initials: I
authors.lastname: da Silva
authors.affiliation: ILL Neutron Facility , Grenoble 38043, France.
authors.forename: Mark
authors.initials: M
authors.lastname: Johnson
authors.affiliation: School of Chemistry, University of Nottingham , University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Carter
authors.affiliation: School of Chemistry, University of Nottingham , University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Ruth
authors.initials: R
authors.lastname: Newby
authors.affiliation: School of Chemistry, University of Nottingham , University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Suyetin
authors.affiliation: School of Chemistry, University of Nottingham , University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Elena
authors.initials: E
authors.lastname: Besley
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory , Chilton, Oxfordshire OX11 0QX, United Kingdom.
authors.forename: Pascal
authors.initials: P
authors.lastname: Manuel
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory , Chilton, Oxfordshire OX11 0QX, United Kingdom.
authors.forename: Svemir
authors.initials: S
authors.lastname: Rudić
authors.affiliation: European Synchrotron Radiation Facility , Grenoble 38043, France.
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Fitch
authors.affiliation: Diamond Light Source , Harwell Science Campus, Oxfordshire OX11 0DE, United Kingdom.
authors.forename: Claire
authors.initials: C
authors.lastname: Murray
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory , Chilton, Oxfordshire OX11 0QX, United Kingdom.
authors.forename: William I F
authors.initials: WI
authors.lastname: David
authors.affiliation: School of Chemistry, University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom.
authors.forename: Sihai
authors.initials: S
authors.lastname: Yang
authors.affiliation: School of Chemistry, University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom.
authors.forename: Martin
authors.initials: M
authors.lastname: Schröder