Crystal Data

Figure 1. Crystal size as a function of aluminum concentration during growth.

Crystals were grown on a point seed in a standard Holden-type (10 L) glass crystallizer. Starting saturation temperature was approximately 64°C and regeneration supersaturation was 0.06. The rotation regime was reversible rotation at 50 rpm (15 s in each direction with a 2 s pause). Growth was continued to maximum size or until the crystal failed. The solution was removed and the crystal was allowed to cool to room temperature before removal from the crystallizer.

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Table 1 shows the growth parameters for 17 crystals:

Crystal Number	[Al] ppm	s	t0	tf	c0	RH	RAB
100	1	0.061	64.3	22.1	0.345	15	24
126	1	0.06	64.5	20	0.3457	14	18
130	5	0.06	64.8	58.9	0.348	12	6
130a	5	0.06	64.4	58.9	0.3453	10	4
131	3	0.06	64	24.7	0.3437	15	16
137	4	0.06	64	58.1	0.3438	15	12
156	3	0.05	64.5	47.2	0.3459	10	7
161	3	0.08	63.8	20	0.3428	20	21
136	4	0.06	63.2	31.7	0.3406	15	15
232	4	0.10	64.7	53.4	0.3466	25	25
232a	4	0.08	64.7	58.4	0.3466
232b	4	0.10	64.7	56.9	0.3466
239	4	0.1	64.4	25	0.3453	27	25
245	5	0.11	64.4	26.7	0.3453	24	23
245a	5	0.10	64.4	56.6	0.3453
245b	5	0.10	64.4	56.6	0.3453
513	3	0.06	61.8	25.2	0.3346	15	15
520	4	0.06	60.1	26.1	0.3277	16	16
132	0	0.06	62.7	37.1	0.3387	12	14
152	0	0.06	64.2	24.1	0.3447	14	18
185	0	0.06	64.1	25.6	0.3441	14	18

Table 1. Growth parameters for KDP crystals grown with 0 to 5 ppm Al³⁺.

All crystals were grown from the point seed and using the rotation regime as in Figure 1. Crystals 513 and 520 were grown in a plastic 20L crystallizer. Supersaturation varied as indicated in the table. However, saturation temperature was approximately 64°C. Growth rate (height and width) is given in cm/day.

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Crystal Number	[Al] ppm	H	A/B	M grams	Comments
100	1	68	95	2040.2	good crystal, no evidence of Al
126	1	93	122	1950.2	good crystal
130	5	25	17	[10]	subindividual crystal
130a	5	17	13	13.7	cracks and inclusions
131	3	101	108	1924	inclusions on pyramid
137	4	41	34	93	subindividual crystal
156	3	96	63	797	inclusions on prism
161	3	86	91	1346	macrosteps on all prisms
136	4	98	94	1471	crack on prism, inclusions on prism
232	4	41	44	430	inclusions and crack on prism
232a	4			[10]	inclusions and crack, remelted
232b	4			[10]	subindividual crystal, remelted
239	4	102	107	1852	clean
245	5	98	105	1751	clean
245a	5			[100]	inclusions and cracks, remelted
245b	5			[20]	subindividual crystal, remelted
513	3	113	119	2642	inclusions on pyramid; 20L crystallizer
520	4	121	110	2595	clean; 20L crystallizer
132	0	67	70	616	crystal on bottom from bad platform
152	0	93	117	1844	perfect
185	0	90	110	1588	good crystal

Table 2. Characteristics of crystals grown with 0 to 5 ppm Al³⁺.

Growth of crystals is indicated in the legend from Table 1 and Figure 1. Brackets indicate masses of crystals which were remelted and thus the masses are calculated values.

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Figure 2. Final crystal shape of KDP crystals grown with 0 to 5 ppm Al^#+.

Crystals were grown as in Figure 1.

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Figure 3. KDP crystals grown at different supersaturation

Crystals were grown as in Figure 1 at 5 ppm Al³⁺. Crystals were regenerated at s=0.06 (1) and 0.11 (2).

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Figure 4. Crystal shape as a function of supersaturation.

Crystals were grown as in Figure 1, except supersaturation varied between 0.05s and 0.11s.

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