Answers are grounded in this paper and cite their sources.
Thin layers of NaNO2 with a thickness of a few μm were grown from the melt on several substrate materials. They have single-crystalline areas of the order of cm2. They exhibit essentially the same dielectric and ferroelectric properties as bulk NaNO2-crystals. The spontaneous polarization is directed preferably perpendicular to the surface of the layer.
No takes yet. Share an insight, caveat, or question.
Vogt et al. (1981) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: