A NEW METHOD TO SOLVE THE S = l/2 HEISENBERG SPIN CHAIN
S=1/2海森堡自旋链的另一种求解方法

We present a new approach which is completely based on the permutation group theory to solve the eigenvalue problem of the S = 1/2 Heisenberg finite-chain with free-ends boundary. All of the eigenvalues and the corresponding eigenstates are obtained. The properties of the ground state and the low-lying excited states of the antiferromagnetic chain are examined.