@article{ISI:000169711900066,
 abstract = {Beginning with a Heisenberg: spin Hamiltonian for the manganese ions in
the Mn12Ac molecule, we find a number of model exact low-energy states
of the system whose spectrum corresponds to the ordering of the states
proposed from experiments. We also obtain the spatial symmetry
classification of the low-lying states and find that none of the
excitations below about 100 K have the same symmetry as the S = 10
ground state. This allows us to restrict ourselves to the S = 10
ground-state manifold in a time-dependent formalism to find the
magnetization of the molecule in the presence of a slowly varying
magnetic field at zero temperature. In our study, we consider the field
sweep rate, fourth-order anisotropic spin interactions, and a transverse
field. We study the effects of these parameters on the magnetization
steps which are known to occur in the hysteresis plots in this system.
We also study the weights of the different states at the magnetization
plateaus as functions of these parameters. We find that the
magnetization plateaus are reproduced even though there are a large
number of states which can tunnel into each other.},
 article-number = {014408},
 author = {Rudra, L and Ramasesha, S and Sen, D},
 doi = {10.1103/PhysRevB.64.014408},
 eissn = {2469-9969},
 issn = {2469-9950},
 journal = {PHYSICAL REVIEW B},
 month = {JUL 1},
 number = {1},
 times-cited = {9},
 title = {Magnetization of Mn-12 acetate in a slowly varying magnetic field: A
quantum mechanical study},
 unique-id = {ISI:000169711900066},
 volume = {64},
 year = {2001}
}