  A general method in constructing a complete set of wave functions for
multipartite identical qubits is presented based on the irreducible
representations of the permutation group and the nth rank tensors. Particular
examples for n =2, 3, and 4 are derived and the entanglement behavior for each
state is examined from several criteria. It is found that the states so
constructed are all bound entangled states. For the case of even n, all the
states are found to have maximum "n-tangle". The symmetry in spin space is
found to increase the n-tangle in general. The "n-tangle" for n = 4 is found
not always representing 4-way entanglement. It measures the degree of
spin-space symmetry instead. A useful relationship in the classification
between systems containing different number of qubits is given in terms of the
Young's Tableaux based on our analysis.
