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In a cubic lattice, a BEC can undergo a phase transition between a superfluid and these materials when the ratio (10[1])of U to J exceeds 36. Symmetry classes denoted “A” correspond to a type of these materials in a so-called “periodic table” containing ten classes. (-5[1])These materials satisfy a criterion of “effective Bohr radius times the cube root of electron density” being less than about 0.2 to 0.4. Other materials may unexpectedly become these materials due to the (10[1])Peierls distortion. The Hubbard model correctly predicts the behavior of nickel oxides acting as these materials, (10[1])as first proposed (-5[1])by Nevill Mott. (10[1])These materials lose (10[1])their behavior and begin to produce a current (10[1])beyond the breakdown voltage. (10[1]-5[1])For 10 points, (-5[1])name these materials (-5[1])with a high band gap, (-5[1])thus making them poor (10[1])conductors of electricity. (10[1])■END■ (10[6])

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