Fig. 1. User interface of ChromWin.

Fig. 2. Flow chart of the calculation path of ChromWin.

Fig. 3. Comparison of the Newton (a) and the improved algorithm (b) for the determination of enantiomerization barriers.

Scheme 1. Equilibria in a theoretical plate: A is the first eluted enantiomer, B is the second eluted enantiomer, k represents the rate constant and K the distribution constant.

Fig. 4. Percentage of the interconverted enantiomer B″ of the sum (A″+B″).

Fig. 5. Difference between the stochastic model (SM; straight line) and the stochastic model+ (SM+; dashed line); input parameters are t_M=1.0 min, t_R^A=20.0 min, t_R^B=21 min, N_A=200 000, N_B=40 000, k₁^stat=1E−3 s⁻¹, k₁^mob=1E−3 s⁻¹.

Fig. 6. Enantiomerization of 1-chloro-2,2-dimethylaziridine.

Fig. 7. Comparison of the experimental and simulated chromatograms of 1-chloro-2,2-dimethylaziridine (DGC): experimental (left; Chirasil-Nickel(II), 25 m, 250 μm (ID), 250 nm film thickness, 67.4°C, 0.2 bar, carrier gas: nitrogen), simulated with the theoretical plate model (centre) and simulated with the stochastic model+ (SM+; right).

Fig. 8. Enantiomerization of oxazepam.

Table 1. Evaluated parameters from the artificial chromatograms in Fig. 5 calculated with the stochastic model (SM) and the stochastic model+ (SM+)

Table 2. Experimental and simulated data of the enantiomerization experiments