Abstract
Structures of excited states in
11
B are investigated with a method of
β
-
γ
constraint antisymmetrized molecular dynamics in combination with the generator coordinate method. Various excited states with developed cluster core structures are suggested in positive- and negative-parity states. For negative-parity states, we suggest a band with a
2α+t
cluster structure. This band starts from the
3/
2
−
3
state and can correspond to the experimental band observed recently. In positive-parity states, two
α
core cluster structures with surrounding nucleons are found. A
K
π
=1/
2
+
band is suggested to be constructed from a remarkably developed cluster structure with a large prolate deformation. We discuss features of the cluster structure in association with molecular orbital structures of
10
Be.