Polymers in Confined Geometry.pdf
Polymers in Confined Geometry.pdf
Polymers in Confined Geometry.pdf
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B.3. PARALLEL END-TO-END DISTANCE CORRELATION 85<br />
with K(x) = e −2x/ld s<strong>in</strong> 2 (x/ld − π/4)). The <strong>in</strong>tegration over K(|τ − τ ′ |) has to<br />
be treated as <strong>in</strong> eq. (B.8).<br />
Evaluat<strong>in</strong>g only the first <strong>in</strong>tegral explicitly<br />
τ<br />
0<br />
dτ ′ K(τ − τ ′ ) = 1<br />
2<br />
τ<br />
dτ<br />
0<br />
′ τ−τ′<br />
−2 l e d<br />
0<br />
and perform<strong>in</strong>g the second <strong>in</strong>tegration gives<br />
s ′<br />
0<br />
dτ<br />
τ<br />
0<br />
dτ ′ K(τ − τ ′ ) = ld<br />
8<br />
<br />
1 − cos<br />
ld<br />
′ τ − τ<br />
2 −<br />
ld<br />
π<br />
<br />
4<br />
= − ld<br />
dx e<br />
4 2τ/ld<br />
−x (1 − s<strong>in</strong> x)<br />
= ld<br />
<br />
2τ<br />
− l 1 + e d −2 + s<strong>in</strong><br />
8<br />
2τ<br />
+ cos 2τ<br />
<br />
, (B.13)<br />
s ′ <br />
2τ<br />
− l dτ 1 + e d −2 + s<strong>in</strong><br />
0<br />
2τ<br />
+ cos<br />
ld<br />
2τ<br />
ld<br />
= l2 2s ′ /ld<br />
d<br />
dτ<br />
16 0<br />
1 − 2e −x + e −x (s<strong>in</strong> x + cos x) <br />
= l2 d<br />
16<br />
2s ′<br />
ld<br />
2s′<br />
− l + e d<br />
ld<br />
<br />
2 − cos 2s′<br />
ld<br />
<br />
ld<br />
<br />
2s′<br />
− l + e d 2 − cos 2s′<br />
ld<br />
<br />
<br />
− 1 . (B.14)<br />
The rema<strong>in</strong><strong>in</strong>g <strong>in</strong>tegrals are treated equivalently. F<strong>in</strong>ally we obta<strong>in</strong> the follow<strong>in</strong>g<br />
result valid for all s and s ′<br />
<br />
R||(s)R||(s ′ ) <br />
= 1 − ld<br />
<br />
ss<br />
2 lp<br />
′ + r||(s)r||(s ′ ) <br />
<br />
= 1 − ld<br />
+<br />
2 lp<br />
l2 d<br />
16 l2 <br />
ss<br />
p<br />
′ + l3 d<br />
32 l2 m<strong>in</strong>(s, s<br />
p<br />
′ )<br />
+ l4 d<br />
128 l2 <br />
− e<br />
p<br />
−2 |s−s′ <br />
|<br />
ld 2 − cos 2 |s − s′ <br />
|<br />
(B.15)<br />
ld<br />
<br />
2s<br />
− l + e d 2 − cos 2s<br />
<br />
<br />
− 1 .<br />
This result is used <strong>in</strong> the l<strong>in</strong>es follow<strong>in</strong>g eq. (3.41).