Table 2. List of stacking events used for disorder modelling in DISCUS and the corresponding interpretation of the local structure.

Event	Δx	Δy	Δz	P ij	Interpretation
α + α	0	0	1	(1 − p x)(1 − p y)	Polymorph I
α + β	0	0	1	p x(1 − p y)	Polymorph II
α + γ	0	0	1.120	p y	Like RUB-6
β + α	0	0	1	p x(1 − p y)	Polymorph II
β + β	0	0	1	(1 − p x)(1 − p y)	Polymorph I
β + γ	0	0	1.120	p y	Like RUB-6
γ + α	0	0	1	(1 − p y)/2	Polymorph I
γ + β	0	0	1	(1 − p y)/2	Polymorph II
γ + γ	0	0	1.120	p y	Like RUB-6