  The spherical-to-prolate shape transition in neutron-rich Cr isotopes from N
= 34 to 42 is studied by solving the collective Schr\"odinger equation for the
five-dimensional quadrupole collective Hamiltonian. The collective potential
and inertial functions are microscopically derived with use of the constrained
Hartree-Fock-Bogoliubov plus local quasiparticle random-phase approximation
method. Nature of the quadrupole collectivity of low-lying states is discussed
by evaluating excitation spectra and electric quadrupole moments and transition
strengths. The result of calculation indicates that Cr isotopes around 64Cr are
prolately deformed but still possess transitional character; large-amplitude
shape fluctuations dominate in their low-lying states.
