| We show that the Valence Bond Crystal Phase of the Kagome-Lattice Heisenberg Model has a small spin-gap and a large number of two-particle singlet bound states. Many of these singlet bound states may fall below the lowest triplet excitation and lead to a weakly dispersive band of low energy singlets. The nature of these singlet excitations for the 36-site cluster and their relevance to low-lying states in the Exact Diagonalization studies will be discussed. |
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