Iodate nitrates are mixed anion compounds that contain both iodate and nitrate anions.
Giant birefringence Iodate nitrates can have high birefringence. The scandium salt has a giant birefringence of 0.348 at 546 nm. When discovered in 2021 it was a record high birefringence for oxyanion compounds, but it was exceeded by CeF2(SO4) just a month later with a value of 0.361 and sodium hydrogen squarate hydrate, NaHC4O4·H2O with a value of 0.52 at 1064 nm. All of these are beaten by hexagonal boron nitride (h-BN) with birefringence of 0.7 in visible light.
List formulanameformula weightsystemspace groupcell ÅvolumedensitycommentsrefAl(IO3)2NO3•6H2Oaluminium diiodate nitrate hexahydratehexagonalP321a=6.764 c=8.09 Z=1KIO3•KNO3•2HIO3dipotassium dihydrogen triiodate nitrateorthorhombicP212121a=7.109 b=10.638 c=15.5Sc(IO3)2(NO3)scandium diiodate nitrate1370.31trigonalR32a=5.3536 c=23.567 Z=1584.963.890colourless; giant birefringence 0.348 at 546 nm; SHG 4.0×KDP; UV edge 298 nm; stable to 360°CIn(IO3)2(NO3)indium diiodate nitrate526.63trigonalR32a=5.2165 c=24.195, γ=120° Z=3570.24.601colourless[In(IO3)(OH)(H2O)](NO3)386.75monoclinicP21/na=5.5756 b=16.410 c=7.734, β=109.95 Z=4665.23.862colourlessLa(IO3)2(NO3)lanthanum diiodate nitratetrigonalP3121a=7.1002 c=38.177 Z=9SHG 0.6 × KDP; band gap 4.23 eVCe(IO3)2(NO3)cerium diiodate nitrate551.93trigonalP3121a=7.0537 c=37.972 Z=91639.85.030SHG 1 × KDPα-Th(IO3)2(NO3)(OH)triclinicPa=6.9581 b=7.2294 c=9.8989 α=68.896° β=88.759° γ=66.620°β-Th(IO3)2(NO3)(OH)orthorhombicPbcaa=7.1459 b=14.140 c=16.612
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