Correlated domain model of deuterated dipole glass

Abstract

The low-frequency dielectric relaxation of the deuterated rubidium ammonium dihydrogen phosphate ͑DRADP͒ dipole glass was investigated by examining the complex dielectric permittivity above the glass freezing temperature. We show that none of the well-known Debye-type relaxation functions that include the Cole-Cole, Cole-Davidson, and Kohlrausch-Williams-Watts functions adequately describe the observed dielectric relaxation behavior of the DRADP. We then examine the Chamberlin's correlated domain model as a possible description of the DRADP dipole glass. The experimental data and the computational results based on the correlated domain model qualitatively agree with each other with common features of ͑i͒ a long tail at the lower-frequency side and ͑ii͒ increase in the asymmetry of ⑀Љ() spectrum with decreasing temperature. Finally, we discuss the fitting results of the DRADP dipole glass in comparison with glass-forming liquids and other polar glasslike systems. ͓S0163-1829͑99͒03034-9͔ PHYSICAL REVIEW B 1 SEPTEMBER 1999-II VOLUME 60, NUMBER 10 PRB 60 0163-1829/99/60͑10͒/7170͑8͒/$15.00 7170

Supercooling Behavior and Dipole-Glass-like Relaxation in a Three-Dimensional Water Framework

“…Furthermore, the significant blocking effect at low temperature may result in trapped “water clusters” and give rise to a dipole glassy behavior. , Indeed, as shown in Figure d, the dielectric relaxation of 1 ·H 2 O in the temperature range of 225–270 K could be well fitted by the Vogel–Fulcher formula that is commonly used in fitting glassy behavior, τ = τ 0 exp­[ E a / k B ( T – T VF )], , where E a is the average fluctuation activation energy, and T VF is the freezing temperature. The fitting results, E a = 0.03 eV and T VF = 192.0 K, suggested that 1 ·H 2 O is more similar to proton dipole glass ( E a ranges from 0.03 to 0.09 eV) , than to amorphous ice ( E a is ca. 0.35 eV and T VF ranges from 116 to 136 K). − The fitting of the dipole glass model suggested that the protons trapped by the blocking effect behave as locally correlated dipole microdomains with random dipole directions and broadly distributed sizes, eventually giving a broadly distributed relaxation time. ,, As complements, the anhydrous phase ( 1 ) showed no significant dielectric anomalies, while the deuterated phase ( 1 ·D 2 O) showed a similar thermal and dielectric anomalies (Figures S9 and S10) with a significantly higher T VF (208 K) and a slightly lower E a (0.02 eV, Figure S10).…”

“…The fitting results, E a = 0.03 eV and T VF = 192.0 K, suggested that 1 ·H 2 O is more similar to proton dipole glass ( E a ranges from 0.03 to 0.09 eV) , than to amorphous ice ( E a is ca. 0.35 eV and T VF ranges from 116 to 136 K). − The fitting of the dipole glass model suggested that the protons trapped by the blocking effect behave as locally correlated dipole microdomains with random dipole directions and broadly distributed sizes, eventually giving a broadly distributed relaxation time. ,, As complements, the anhydrous phase ( 1 ) showed no significant dielectric anomalies, while the deuterated phase ( 1 ·D 2 O) showed a similar thermal and dielectric anomalies (Figures S9 and S10) with a significantly higher T VF (208 K) and a slightly lower E a (0.02 eV, Figure S10).…”

“…29,32 Indeed, as shown in Figure 4d, the dielectric relaxation of 1•H 2 O in the temperature range of 225−270 K could be well fitted by the Vogel−Fulcher formula that is commonly used in fitting glassy behavior, τ = τ 0 exp[E a / k B (T − T VF )], 22,23 where E a is the average fluctuation activation energy, and T VF is the freezing temperature. The fitting results, E a = 0.03 eV and T VF = 192.0 K, suggested that 1•H 2 O is more similar to proton dipole glass (E a ranges from 0.03 to 0.09 eV) 24,25 than to amorphous ice (E a is ca. 0.35 eV and T VF ranges from 116 to 136 K).…”

“…The dynamic behavior of water has attracted considerable attention over time due to the fundamental importance of water in geological/biological processes and solid-state chemistry. − In addition to the crystalline ices and relevant dynamics, the glassy ice resulting from the collapse of the long-range order in atomic positions has been intensively studied in recent decades. − Recently, another novel glassy behavior caused by the collapse of long-range order of dipoles (dipole glass) was revealed in many crystalline compounds, − increasing our understanding of the complex dynamic behaviors. In this sense, to study the dipole-glass behaviors in crystalline ices can provide a new perspective to enrich our knowledge of the dipole dynamic behavior of solid water.…”

Coexistence of two universal relaxations in the glassy freezing of a deuteron dipole glass

“…Glass is well known to show a slow-relaxation dynamics of nonexponential decay with a universality described by either Kohlrausch-Williams-Watts (KWW) stretched-exponential decay function φ(t) = φ 0 exp[−(t/τ ) β ] (0 < β < 1) or Curie-von Schweidler (CvS) power law decay function φ(t) = φ 0 (t/τ ) −α (0 < α < 2) [1][2][3][4][5]. Dipole glass has been introduced as a model system of glass transition, possibly illuminating more details from wider ranges of experimental accessibilities than spin glass systems [6][7][8][9][10].…”