title: Long-wavelength transverse modes in charged colloidal crystals.
abstract: The dynamics of closely index matched colloidal crystals of charged silica spheres dispersed in deionized ethylene glycol-water mixture is investigated using dynamic light scattering. At variance with the reports of phonon dispersion measurements on thin colloidal crystals, our observations on millimeter-sized crystals show unambiguous evidence for overdamped transverse modes turning propagative in the range of small wave numbers in agreement with the theory of hydrodynamic interactions in charged colloidal crystals.
authors.affiliation: Materials Science Division, Indira Gandhi Centre for Atomic Research, Kalpakkam -603 102, Tamil Nadu, India.
authors.forename: B V R
authors.initials: BV
authors.lastname: Tata
authors.forename: P S
authors.initials: PS
authors.lastname: Mohanty
authors.forename: M C
authors.initials: MC
authors.lastname: Valsakumar
authors.forename: J
authors.initials: J
authors.lastname: Yamanaka
mesh_terms: D003102:Colloids / Q000032:analysis / Q000737:chemistry*; D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D019855:Ethylene Glycol / Q000737:chemistry*; D008863:Microspheres; D008956:Models, Chemical; D008968:Molecular Conformation; D044367:Phase Transition; D011208:Powders; D012822:Silicon Dioxide / Q000737:chemistry*; D012996:Solutions; D055672:Static Electricity; D014783:Viscosity
chemical_list: D003102:Colloids; D011208:Powders; D012996:Solutions; D012822:Silicon Dioxide; D019855:Ethylene Glycol