<s>
In	O
statistical	O
mechanics	O
,	O
the	O
corner	B-Algorithm
transfer	I-Algorithm
matrix	I-Algorithm
describes	O
the	O
effect	O
of	O
adding	O
a	O
quadrant	O
to	O
a	O
lattice	O
.	O
</s>
<s>
Introduced	O
by	O
Rodney	O
Baxter	O
in	O
1968	O
as	O
an	O
extension	O
of	O
the	O
Kramers-Wannier	O
row-to-row	O
transfer	O
matrix	O
,	O
it	O
provides	O
a	O
powerful	O
method	O
of	O
studying	O
lattice	B-Algorithm
models	I-Algorithm
.	O
</s>
<s>
a	O
square	O
lattice	B-Algorithm
model	I-Algorithm
with	O
a	O
spin	O
σi	O
assigned	O
to	O
each	O
site	O
i	O
and	O
interactions	O
limited	O
to	O
spins	O
around	O
a	O
common	O
face	O
.	O
</s>
<s>
The	O
matrix	O
A	O
,	O
then	O
,	O
is	O
the	O
corner	B-Algorithm
transfer	I-Algorithm
matrix	I-Algorithm
for	O
the	O
given	O
lattice	O
quadrant	O
.	O
</s>
<s>
A	O
corner	B-Algorithm
transfer	I-Algorithm
matrix	I-Algorithm
A2m	O
(	O
defined	O
for	O
an	O
m×m	O
quadrant	O
)	O
may	O
be	O
expressed	O
in	O
terms	O
of	O
smaller	O
corner	O
transfer	O
matrices	O
A2m-1	O
and	O
A2m-2	O
(	O
defined	O
for	O
reduced	O
(	O
m-1	O
)	O
×( 	O
m-1	O
)	O
and	O
(	O
m-2	O
)	O
×( 	O
m-2	O
)	O
quadrants	O
respectively	O
)	O
.	O
</s>
<s>
This	O
recursion	O
relation	O
allows	O
,	O
in	O
principle	O
,	O
the	O
iterative	O
calculation	O
of	O
the	O
corner	B-Algorithm
transfer	I-Algorithm
matrix	I-Algorithm
for	O
any	O
lattice	O
quadrant	O
of	O
finite	O
size	O
.	O
</s>
<s>
it	O
is	O
diagonalisable	O
by	O
an	O
orthogonal	B-Algorithm
matrix	I-Algorithm
)	O
.	O
</s>
