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Energy gap, effective mass, and critical phenomena in NaNO 2 crystal
Author(s) -
ElDib A. M.,
Hassan H. F.
Publication year - 1986
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.2221350126
Subject(s) - condensed matter physics , effective mass (spring–mass system) , band gap , dielectric , phase transition , valence (chemistry) , materials science , thermal conduction , range (aeronautics) , crystal (programming language) , thermal , thermodynamics , physics , quantum mechanics , optoelectronics , composite material , computer science , programming language
The effect of thermal expansion on the energy gap of NaNO 2 is studied. An attempt is made to estimate the effect of thermal vibrations on the energy gap. The temperature dependence of the effective mass in the conduction and valence bands is also studied. The energy gap shows a non‐linearity near the phase transition region. A sudden change is also observed at about 3 K above T c . Both the effective masses show some oscillations in a wide range of temperature (from ∼ 140 to ∼220 °C). The results of the energy gap and the effective mass give evidence that a new phase transition exists at about 3 K above T c . They also give an interpretation for the deviation of the dielectric constant from the Curie‐Weiss law.