title: Atomic Number Dependent "Structural Transitions" in Ordered Lanthanide Monolayers: Role of the Hydration Shell.
abstract: When lanthanide ions are present in the aqueous subphase of a floating monolayer (Langmuir film), the ions attracted to the interface will in many cases form commensurate and/or incommensurate two-dimensional structures. These lattices depend not only on the molecules forming the monolayer, but also on the atomic number of the lanthanide, with a sudden change between the lattice formed by lighter ions and that formed by heavier ions under a given monolayer. Since there are few other relevant differences between the lanthanides, we attribute the Z-dependent "transition" to the number of water molecules associated with each ion. The first hydration shell is thought to vary continuously from ∼9 in lighter lanthanides to ∼8 in heavier lanthanides.
authors.affiliation: Department of Physics & Astronomy, Northwestern University , Evanston, Illinois 60208, United States.
authors.forename: Mitchell
authors.identifier: 0000-0001-7266-1092
authors.initials: M
authors.lastname: Miller
authors.affiliation: Department of Physics & Astronomy, Northwestern University , Evanston, Illinois 60208, United States.
authors.forename: Miaoqi
authors.initials: M
authors.lastname: Chu
authors.affiliation: Center for Advanced Radiation Sources, University of Chicago , Chicago, Illinois 60637, United States.
authors.forename: Binhua
authors.identifier: 0000-0001-5932-4905
authors.initials: B
authors.lastname: Lin
authors.affiliation: Center for Advanced Radiation Sources, University of Chicago , Chicago, Illinois 60637, United States.
authors.forename: Wei
authors.identifier: 0000-0002-9996-3733
authors.initials: W
authors.lastname: Bu
authors.affiliation: Department of Physics & Astronomy, Northwestern University , Evanston, Illinois 60208, United States.
authors.forename: Pulak
authors.identifier: 0000-0002-2111-0546
authors.initials: P
authors.lastname: Dutta