How reliable is this method to estimate the ratio of the two components in a racemic mixture?
There is no experience with crystals that are inversion twins. If you have interesting samples, we would like to hear from you. There is one check you can do yourself even if you are not able to share your data with us: Before trusting an off-zero value of y you should examine the PLATON output very carefully. It is essential that the normal probability plot has a good correlation coefficient and a slope around 1.0 (see also related questions above).
There is very little experience with crystals that are inversion twins, and none with crystals for which the twin ratio had been determined using other means. Values are typically comparable to the Flack values. If you have interesting samples, we would like to hear from you. There is one check you can do yourself even if you are not able to share your data with us: Before trusting an off-zero value of y you should examine the PLATON output very carefully. It is essential that the normal probability plot has a good correlation coefficient and a slope around 1.0 (see also related questions above).
