Chemistry Reference
In-Depth Information
a
√
3
2. Note that in the case of structured walls, the commensurate
confinement is achieved by putting the two rows of fixed particles t
ha
t are just adja-
cent to the rows of mobile particles at a distance
D
=
(
D
=
(
n
x
−
)
/
a
√
3
n
x
+
1
)(
/
2
)
, of course;
a
√
3
now this distance rather is
D
=
(
n
x
+
1
−
)(
/
2
)
.
When we start the system at
=
0 and increase
in small steps (
=
0
.
25),
equilibrating at each value of
further, we
can monitor the stress-strain characteristics of the system (Fig.
1.10
). As expected,
for
the system carefully before increasing
=
0 the crystal is stress free, and for
>
0 the stress increases linearly
with
0 we observe a jump in the stress-strain curve, where the stress
suddenly decreases strongly: inspection of the system configuration reveals that a
transition
n
x
.At
=
2
.
→
n
x
−
1 in the number of rows parallel to the confining boundaries
Fig. 1.10
Internal stress
σ
=
σ
−
σ
xx
(in Lennard-Jones units) at
k
B
T
/ε
=
1
.
0 in the confined
yy
crystalline strip plotted vs.
, for the case of a system started with
n
x
=
30,
n
y
=
108 (
full
symbols
) and a system started with
n
x
108 (plus the 108 extra particles appropriately
distributed in the 29 rows, as described in the text (
open symbols
)).
Curves
are guides to the eye
only. The
upper insert
shows a schematic sketch of the geometry, the frozen particles being shown
as
shaded circles
, mobile particles are
not shaded
=
29,
n
y
=
