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１９２８年Ｅｌｉｎｇ和Ｔｅｒｐｓｔｒａ未发现Ｋ２Ｃｒ２Ｏ７晶体具有压电效应；而１９３０年Ｓｔｅｄｅｈｏｕｄｅｒ和Ｔｅｒｐｓｔｒａ发现了Ｋ２Ｃｒ２Ｏ７晶体在（００１－）面上并未发生粗糙化。１９３１年Ｓｈｕｂｎｉｋｏｖ发表了一组照片，清楚地呈现了Ｋ２Ｃｒ２Ｏ７晶体的（００１）面和（００１－）面具有不对称和不同的结构。１９３２年Ｓｃｈｏｅｐ根据腐蚀坑提出了对称中心存在的假说。１９３５年Ｇｒｅｅｎｗｏｏｄ采用极灵敏仪器也未能确定压电效应。１９５４年和１９５５年Ｐｏｄｉｓｋｏ和Ｓｈｕｂｎｉｋｏｖ再一次指出Ｋ２Ｃｒ２Ｏ７晶体在（００１）面和（００１－）面的不对称腐蚀行为。１９５９年Ｒａｏ用Ｘ射线方法研究了Ｋ２Ｃｒ２Ｏ７晶体，通过统计衍射强度得出结论，Ｋ２Ｃｒ２Ｏ７晶体有一对称中心。１９６４年Ｐａｒｖｏｖ和Ｓｈｕｂｎｉｋｏｖ生长了一块自由悬浮的晶体，６个月内温度逐渐从３０．４℃降低到２９．２℃，（００１－）和（１００）的生长速率是０，再次确定了结构不对称。１９７０年Ｖａｄｉｌｏ认为过饱和度对不对称生长有影响。低过饱和度时两个｛００１｝都光滑，适中过饱和度下靠近容器底部的｛００１｝面粗糙，高过饱和度导致两个｛００１｝都粗糙?
In 1928, Eling and Terpstra did not find the piezoelectric effect of K2Cr2O7 crystals; in 1930 Stedehouder and Terpstra found that K2Cr2O7 crystals did not appear to be roughened on the (001-) surface. In 1931 Shubnikov published a series of photographs clearly showing that the (001) and (001-) planes of K2Cr2O7 have asymmetric and different structures. In 1932 Schoep proposed the hypothesis of the existence of symmetry centers based on the corrosion pits. In 1935, Greenwood also used very sensitive instruments to determine the piezoelectric effect. In 1954 and 1955, Podisko and Shubnikov again pointed out the asymmetric corrosion behavior of K2Cr2O7 crystals on the (001) and (001-) planes. In 1959, Rao studied the crystal of K2Cr2O7 by X-ray method. According to the statistical diffraction intensity, K2Cr2O7 crystal has a symmetrical center. Parvov and Shubnikov grew a free-floating crystal in 1964, gradually decreasing the temperature from 30.4 ° C to 29.2 ° C within 6 months, and the growth rates of (001-) and (100) were 0, again confirming that the structure was not symmetry. 1970 Vadilo that supersaturation has an impact on asymmetric growth. Both {001} are smooth at low over-saturation, rough on the {001} surface near the bottom of the container at moderate supersaturation, and high over-saturation results in both {001} being rough.