Loading…
Heat capacity, thermal expansion and barocaloric effect in fluoride K2TaF7
The heat capacity and thermal expansion of potassium heptafluorotantalate were studied. The room temperature phase P 2 1 / c is stable at least to 4 K. The strong first-order phase transition P 2 1 / c - P n m a at T 0 = 486.2 K is accompanied by giant changes in the entropy, Δ S 0 = 22.3 J ( mol K...
Saved in:
Published in: | Journal of materials science 2019-12, Vol.54 (23), p.14287-14295 |
---|---|
Main Authors: | , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | The heat capacity and thermal expansion of potassium heptafluorotantalate were studied. The room temperature phase
P
2
1
/
c
is stable at least to 4 K. The strong first-order phase transition
P
2
1
/
c
-
P
n
m
a
at
T
0
=
486.2
K
is accompanied by giant changes in the entropy,
Δ
S
0
=
22.3
J
(
mol
K
)
-
1
,
and volume strain,
δ
V
0
/
V
=
-
3.6
%
. A rather high sensitivity of
K
2
TaF
7
to pressure was found,
d
T
0
/
d
p
=
-
220
K
G
Pa
-
1
. Significant extensive and intensive barocaloric effects are found at low pressure. The possibility of improving the barocaloric properties is discussed. |
---|---|
ISSN: | 0022-2461 1573-4803 |
DOI: | 10.1007/s10853-019-03924-8 |