The Birman–Murakami–Wenzl Algebras of Type D_n

The Birman–Murakami–Wenzl algebra (BMW algebra) of type D_n is shown to be semisimple and free of rank (2^n + 1)n!! − (2^n−1 + 1)n! over a specified commutative ring R, where n!! =1·3…(2n − 1). We also show it is a cellular algebra over suitable ring extensions of R. The Brauer algebra of type D_n is the image of an R-equivariant homomorphism and is also semisimple and free of the same rank, but over the ring ℤ[δ^(±1)]. A rewrite system for the Brauer algebra is used in bounding the rank of the BMW algebra above. As a consequence of our results, the generalized Temperley–Lieb algebra of type D_n is a subalgebra of the BMW algebra of the same type.