Amorphous polymorphism in ice investigated by inelastic neutron scattering

H. Schober, M. Koza, A. Tölle, F. Fujara, Charles Angell, R. Böhmer

Research output: Contribution to journalArticle

40 Citations (Scopus)

Abstract

High-density Ihda and low-density Ilda amorphous ice phases have been investigated by inelastic neutron scattering (INS) with emphasis on the energy window from 0.5 to 20 meV. At variance with earlier measurements the spectra in the Ihda phase show a simple ω2 behaviour in the acoustic region and the temperature dependence is found to be harmonic. Ihda converts with a strongly temperature-dependent rate towards Ilda ice. We have investigated in detail the time evolution of both the static and dynamic response functions at several temperatures. Elastic small-angle signals indicate the presence of strong heterogeneities at the early stages of the conversion process. At least two different time scales are present in the transition. The structural changes are reflected in the frequency distribution. The first peak in the phonon density-of-states softens appreciably when going from Ihda to Ilda. In the acoustic region there is evidence that Ilda is softer than both Ihda and crystalline cubic ice Ic. No signs of a fast ps process related to melting can be detected in the dynamics.

Original languageEnglish (US)
Pages (from-to)897-902
Number of pages6
JournalPhysica B: Condensed Matter
Volume241-243
StatePublished - 1997

Fingerprint

Inelastic neutron scattering
polymorphism
Ice
Polymorphism
inelastic scattering
ice
neutron scattering
Acoustics
acoustics
frequency distribution
dynamic response
Temperature
Dynamic response
Melting
melting
Crystalline materials
harmonics
temperature dependence
temperature
energy

Keywords

  • Amorphous ice
  • Ice
  • Polymorphism

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Schober, H., Koza, M., Tölle, A., Fujara, F., Angell, C., & Böhmer, R. (1997). Amorphous polymorphism in ice investigated by inelastic neutron scattering. Physica B: Condensed Matter, 241-243, 897-902.

Amorphous polymorphism in ice investigated by inelastic neutron scattering. / Schober, H.; Koza, M.; Tölle, A.; Fujara, F.; Angell, Charles; Böhmer, R.

In: Physica B: Condensed Matter, Vol. 241-243, 1997, p. 897-902.

Research output: Contribution to journalArticle

Schober, H, Koza, M, Tölle, A, Fujara, F, Angell, C & Böhmer, R 1997, 'Amorphous polymorphism in ice investigated by inelastic neutron scattering', Physica B: Condensed Matter, vol. 241-243, pp. 897-902.
Schober H, Koza M, Tölle A, Fujara F, Angell C, Böhmer R. Amorphous polymorphism in ice investigated by inelastic neutron scattering. Physica B: Condensed Matter. 1997;241-243:897-902.
Schober, H. ; Koza, M. ; Tölle, A. ; Fujara, F. ; Angell, Charles ; Böhmer, R. / Amorphous polymorphism in ice investigated by inelastic neutron scattering. In: Physica B: Condensed Matter. 1997 ; Vol. 241-243. pp. 897-902.
@article{1b167ea38c2c49be9e021f8a831681c1,
title = "Amorphous polymorphism in ice investigated by inelastic neutron scattering",
abstract = "High-density Ihda and low-density Ilda amorphous ice phases have been investigated by inelastic neutron scattering (INS) with emphasis on the energy window from 0.5 to 20 meV. At variance with earlier measurements the spectra in the Ihda phase show a simple ω2 behaviour in the acoustic region and the temperature dependence is found to be harmonic. Ihda converts with a strongly temperature-dependent rate towards Ilda ice. We have investigated in detail the time evolution of both the static and dynamic response functions at several temperatures. Elastic small-angle signals indicate the presence of strong heterogeneities at the early stages of the conversion process. At least two different time scales are present in the transition. The structural changes are reflected in the frequency distribution. The first peak in the phonon density-of-states softens appreciably when going from Ihda to Ilda. In the acoustic region there is evidence that Ilda is softer than both Ihda and crystalline cubic ice Ic. No signs of a fast ps process related to melting can be detected in the dynamics.",
keywords = "Amorphous ice, Ice, Polymorphism",
author = "H. Schober and M. Koza and A. T{\"o}lle and F. Fujara and Charles Angell and R. B{\"o}hmer",
year = "1997",
language = "English (US)",
volume = "241-243",
pages = "897--902",
journal = "Physica B: Condensed Matter",
issn = "0921-4526",
publisher = "Elsevier",

}

TY - JOUR

T1 - Amorphous polymorphism in ice investigated by inelastic neutron scattering

AU - Schober, H.

AU - Koza, M.

AU - Tölle, A.

AU - Fujara, F.

AU - Angell, Charles

AU - Böhmer, R.

PY - 1997

Y1 - 1997

N2 - High-density Ihda and low-density Ilda amorphous ice phases have been investigated by inelastic neutron scattering (INS) with emphasis on the energy window from 0.5 to 20 meV. At variance with earlier measurements the spectra in the Ihda phase show a simple ω2 behaviour in the acoustic region and the temperature dependence is found to be harmonic. Ihda converts with a strongly temperature-dependent rate towards Ilda ice. We have investigated in detail the time evolution of both the static and dynamic response functions at several temperatures. Elastic small-angle signals indicate the presence of strong heterogeneities at the early stages of the conversion process. At least two different time scales are present in the transition. The structural changes are reflected in the frequency distribution. The first peak in the phonon density-of-states softens appreciably when going from Ihda to Ilda. In the acoustic region there is evidence that Ilda is softer than both Ihda and crystalline cubic ice Ic. No signs of a fast ps process related to melting can be detected in the dynamics.

AB - High-density Ihda and low-density Ilda amorphous ice phases have been investigated by inelastic neutron scattering (INS) with emphasis on the energy window from 0.5 to 20 meV. At variance with earlier measurements the spectra in the Ihda phase show a simple ω2 behaviour in the acoustic region and the temperature dependence is found to be harmonic. Ihda converts with a strongly temperature-dependent rate towards Ilda ice. We have investigated in detail the time evolution of both the static and dynamic response functions at several temperatures. Elastic small-angle signals indicate the presence of strong heterogeneities at the early stages of the conversion process. At least two different time scales are present in the transition. The structural changes are reflected in the frequency distribution. The first peak in the phonon density-of-states softens appreciably when going from Ihda to Ilda. In the acoustic region there is evidence that Ilda is softer than both Ihda and crystalline cubic ice Ic. No signs of a fast ps process related to melting can be detected in the dynamics.

KW - Amorphous ice

KW - Ice

KW - Polymorphism

UR - http://www.scopus.com/inward/record.url?scp=4244155547&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=4244155547&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:4244155547

VL - 241-243

SP - 897

EP - 902

JO - Physica B: Condensed Matter

JF - Physica B: Condensed Matter

SN - 0921-4526

ER -