Dielectric spectra of the β relaxation in glassy and ultraviscous liquid diethyl phthalate show that its relaxation strength Δϵβ, the distribution of times, and the relaxation rate are more sensitive to temperature T in the ultraviscous liquid than in the glassy state. The Δϵβ against temperature plot has an elbow-shaped break near Tg of 181K, which is remarkably similar to that observed in the entropy, enthalpy, and volume against temperature plots, and in the plot of Δϵβ against the liquid’s entropy minus its 0K value. The ratio of Δϵβ to diethyl phthalate’s entropy, after subtracting the 0K value, is 1.08×103molKJ in the glassy state at 120.4K, which decreases slowly to 0.81×103molKJ at 176K near Tg and thereafter rapidly increases to 1.57×103molKJ at 190K. Variation in Δϵβ parallels the variation of the entropy. A change in the activation energy of the β process at T>Tg indicates that its rate is also determined by the structure of the ultraviscous liquid. Features of β relaxation are consistent with localized motions of molecules and may not involve small-angle motions of all molecules.

1.
G. P.
Johari
,
G.
Power
, and
J. K.
Vij
,
J. Chem. Phys.
116
,
5908
(
2002
).
2.
S. S.
Chang
and
A. B.
Bestul
,
J. Chem. Phys.
56
,
503
(
1972
).
3.
S. S.
Chang
,
J. A.
Horman
, and
A. B.
Bestul
,
J. Res. Natl. Bur. Stand., Sect. A
71A
,
293
(
1967
).
4.
G. P.
Johari
and
M.
Goldstein
,
J. Chem. Phys.
53
,
2372
(
1970
).
5.
G. P.
Johari
and
M.
Goldstein
,
J. Chem. Phys.
55
,
4245
(
1971
).
6.
S.
Pawlus
,
M.
Paluch
,
M.
Sekula
,
K. L.
Ngai
,
S. J.
Rzoska
, and
J.
Ziolo
,
Phys. Rev. E
68
,
021503
(
2003
).
7.
K. L.
Ngai
and
M.
Paluch
,
J. Chem. Phys.
120
,
857
(
2004
).
8.
H.
Fujimori
and
M.
Oguni
,
J. Chem. Thermodyn.
26
,
367
(
1994
).
9.
H.
Fujimori
and
M.
Oguni
,
Solid State Commun.
94
,
157
(
1995
).
10.
H.
Fujimori
,
M.
Mizukami
, and
M.
Oguni
,
J. Non-Cryst. Solids
204
,
38
(
1996
).
11.
S. V.
Nemilov
and
G. P.
Johari
,
Philos. Mag.
83
,
3117
(
2003
);
S. V.
Nemilov
and
G. P.
Johari
,
Philos. Mag.
84
,
845
(
2004
).
12.
J. P.
Joule
, Memr. Manchester Literary Phil. Soc.
3
,
292
(
1867
);
The Scientific Papers of J. P. Joule
(
London Physical Society
, London,
1884
), Vol.
1
, p.
558
.
13.
M.
Goldstein
,
Ann. N.Y. Acad. Sci.
279
,
68
(
1976
).
14.
M.
Goldstein
,
J. Chem. Phys.
64
,
4767
(
1976
).
15.
G. P.
Johari
,
Ann. N.Y. Acad. Sci.
279
,
102
(
1976
).
16.
G. P.
Johari
,
Philos. Mag. B
41
,
41
(
1980
).
17.
G. P.
Johari
,
J. Chem. Phys.
112
,
7518
(
2000
).
18.
G. P.
Johari
,
Ann. N.Y. Acad. Sci.
279
,
117
(
1976
).
19.
J.
Bartoš
,
in Encyclopedia of Analytical Chemistry
, edited by
R. A.
Meyers
(
Wiley
, Chichester,
2000
), p.
7968
.
20.
J.
Bartoš
,
O.
Šauša
,
J.
Krištiak
,
T.
Blochowicz
, and
E.
Rössler
,
J. Phys.: Condens. Matter
13
,
11473
(
2001
).
21.
J.
Bartoš
,
O.
Šauša
,
P.
Bandzuch
,
J.
Zrubcová
, and
J.
Krištiak
,
J. Non-Cryst. Solids
307–310
,
417
(
2002
).
22.
J.
Bartoš
,
O.
Šauša
,
D.
Račko
,
J.
Krištiak
, and
J. J.
Fontanella
,
J. Non-Cryst. Solids
351
,
2599
(
2002
).
23.
J.
Bartoš
,
O.
Šauša
,
P.
Pustková
,
J.
Shánělová
,
J.
Krištiak
, and
J.
Málek
,
J. Non-Cryst. Solids
351
,
1082
(
2005
).
24.
J. T.
Bendler
,
J. J.
Fontanella
,
M. F.
Schlesinger
,
J.
Bartoš
,
O.
Šauša
, and
J.
Krištiak
,
Phys. Rev. E
71
,
031508
(
2005
).
25.
D.
Račko
,
R.
Chelli
,
G.
Cardeni
,
J.
Bartoš
, and
S.
Califano
,
Eur. Phys. J. D
32
,
289
(
2005
).
26.
G.
Power
, Ph.D. thesis,
University of Dublin
, Ireland,
2005
.
27.
S.
Havriliak
, Jr.
and
S.
Negami
,
J. Polym. Sci., Part C: Polym. Symp.
14
,
99
(
1966
).
28.
O. E.
Kalinovskaya
and
J. K.
Vij
,
J. Chem. Phys.
112
,
3262
(
2000
).
29.
G. P.
Johari
,
G.
Power
, and
J. K.
Vij
,
J. Chem. Phys.
117
,
1714
(
2002
).
30.
G.
Power
,
G. P.
Johari
, and
J. K.
Vij
,
J. Chem. Phys.
119
,
435
(
2003
).
31.
K. S.
Cole
and
R. H.
Cole
,
J. Chem. Phys.
9
,
341
(
1941
).
32.
D. W.
Davidson
and
R. H.
Cole
,
J. Chem. Phys.
19
,
1484
(
1951
).
33.
C.
Hansen
,
F.
Stickel
,
T.
Berger
,
R.
Richert
, and
E. W.
Fischer
,
J. Chem. Phys.
107
,
1086
(
1997
).
34.
T.
Fujima
,
H.
Frusawa
, and
K.
Ito
,
Phys. Rev. E
66
,
031503
(
2002
).
35.
G. W.
Scherer
,
Relaxations in Glass and Composites
(
Wiley
, New York,
1986
), Chap. 12.
36.
B. D.
Malhotra
and
R. A.
Pethrick
,
J. Chem. Soc., Faraday Trans. 2
78
,
297
(
1982
).
37.
R.
Simha
,
J. M.
Roe
, and
V. S.
Nanda
,
J. Appl. Phys.
43
,
4312
(
1972
).
38.
G. P.
Johari
,
J. Chem. Phys.
77
,
4619
(
1982
), and references therein.
39.
M.
Vogel
,
C.
Tschirwitz
,
G.
Schnieder
,
C.
Koplin
,
P.
Medick
, and
E.
Rössler
,
J. Non-Cryst. Solids
307–310
,
326
(
2002
).
40.
A.
Döß
,
M.
Paluch
,
H.
Sillescu
, and
G.
Hinze
,
J. Chem. Phys.
117
,
6582
(
2002
).
41.
G. P.
Johari
,
J. Non-Cryst. Solids
307–310
,
317
(
2002
).
42.
T.
Ichitsubo
,
E.
Matasubara
,
T.
Yamamoto
,
H. S.
Chen
,
N.
Nishiyama
,
J.
Saida
, and
K.
Anazawa
,
Phys. Rev. Lett.
95
,
245501
(
2005
).
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