  We propose a simple one-dimensional spin-2 Hamiltonian, which exhibits two
topologically distinct valence bond solid states in different exactly solvable
limits. We then construct the phase diagram and study the quantum phase
transition between these states using the infinite time evolving block
decimation algorithms. From the scaling relation between the entanglement
entropy and correlation length, we find that the central charge for the
underlying critical conformal field theory is $c=2$.
