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Coordination nano-space as stage of hydrogen ortho-para conversion.

ABSTRACT: The ability to design and control properties of nano-sized space in porous coordination polymers (PCPs) would provide us with an ideal stage for fascinating physical and chemical phenomena. We found an interconversion of nuclear-spin isomers for hydrogen molecule H2 adsorbed in a Hofmann-type PCP, {Fe(pz)[Pd(CN)4]} (pz=pyrazine), by the temperature dependence of Raman spectra. The ortho (o)-para (p) conversion process of H2 is forbidden for an isolated molecule. The charge density study using synchrotron radiation X-ray diffraction reveals the electric field generated in coordination nano-space. The present results corroborate similar findings observed on different systems and confirm that o-p conversion can occur on non-magnetic solids and that electric field can induce the catalytic hydrogen o-p conversion.

SUBMITTER: Kosone T

PROVIDER: S-EPMC4632575 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Coordination nano-space as stage of hydrogen ortho-para conversion.

Kosone Takashi T Hori Akihiro A Nishibori Eiji E Kubota Yoshiki Y Mishima Akio A Ohba Masaaki M Tanaka Hiroshi H Kato Kenichi K Kim Jungeun J Real José Antonio JA Kitagawa Susumu S Takata Masaki M

Royal Society open science 20150729 7

The ability to design and control properties of nano-sized space in porous coordination polymers (PCPs) would provide us with an ideal stage for fascinating physical and chemical phenomena. We found an interconversion of nuclear-spin isomers for hydrogen molecule H2 adsorbed in a Hofmann-type PCP, {Fe(pz)[Pd(CN)4]} (pz=pyrazine), by the temperature dependence of Raman spectra. The ortho (o)-para (p) conversion process of H2 is forbidden for an isolated molecule. The charge density study using sy ...[more]

PMID: 26587262

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