11 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 Crystal Properties 4SO2Influence of Doping on K Tariq A.Al- Dahair Maryam E.Al-Mahdawy Dept. of physics/College of Education for Pure Science (Ibn Al- Haitham)/University of Baghdad Received in:22June 2014Accepted in:15September2014 Abstract Single crystals of pure and Cu+2,Fe+2 doped potassium sulfate were grown from aqueous solutions by the slow evaporation technique at room temperature. with dimension of (11x9 x4)mm3 and ( 10x 8x 5)mm3 for crystal doping with Cu &Fe respectively. The influence of doping on crystal growth and its structure revealed a change in their lattice parameters(a=7.479 Å ,b=10.079 Å ,c=5.772 Å)for pure and doping (a=9.687 Å, b=14.926 Å ,c= 9.125 Å) & (a=9.638 Å , b= 8.045 Å ,c=3.271 Å) for Cu & Fe respectively. Structure analysis of the grown crystals were obtained by X-Ray powder diffraction measurements. The diffraction patterns were analyzed by the Rietveld refinement method. Rietveld refinement plots for showing the experimental (red circles)calculated (black line) and difference profiles (blue line); green tick marks indicate reflection positions XRD measurements show the crystal system of orthorhombic. Key words: crystal growth, K2SO4 , doping , Cu+2 ,Fe+2 X-ray diffraction, Differential scanning calorimetric (DSC). 12 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 Introduction The basis of various technology advancement is the crystal growth. The control of the grown crystal during crystallization is very important to the industry. Grown under different conditions and also by different methods like, melt growth , vapor phase growth ,solution growth and gel growth ,are described by [1] and references there in . solution growth aqueous is one of the most efficient and simplest processes which can be employed for crystal growth .In addition The ease in handling and the readiness in its miscibility with the solvents make it an attractive technique for crystal growth. A number of factors such as degree of saturation ,type of solvent ,presence of impurities and the change in growth conditions presumably affect significantly the morphology and properties of the crystal [2] . Potassium sulfate crystals are used in the field of analytical chemistry as reagent medicine, manufacture of glass and feed additive .Potassium sulfate (PS) K2SO4belongs at room temperature to the orthorhombic space group D2h16=(Pnma) and has four formula units per unit cell, with lattice parameters ,a= 7.476 Å, b= 10.071 Å and c= 5.763 Å [3]. The substance transforms upon heating at Tt ≈587 °C into a hexagonal structure D6h4 =P63/mmc with a=5.92 Å and c=8.182 Å where the oxygen positions of the SO4-2tetrahedra are only partially occupied [4]. The hexagonal high temperature phase of the crystal is known asα-K2SO4and the orthorhombic phase as β-K2SO4. Analogous phase transformations (PT’)from α- to β-type phase are shown for the other K2SO4-family crystals (e.g. Na2SO4, like K2CrO4, and K2SeO4) [5, 6]. Another PT of second order at the temperature of 56 K was detected in K2SO4crystal. The crystal symmetry of this low temperature phase (γ-K2SO4) is assumed to be of monoclinic [7]. Recently ,the addition of Cd+2 to the nutrient solution during K2SO4Crystal [8].Due to useful application of doping it is worthy to work on doping of K2SO4. Doping is possible if a suitable host can be found. The cupric ion and ferrate ion can be doped in the K2SO4 crystal, but the degree of application of the data to the pure (Cu ;Fe)2SO4 system depends very highly on the nature of the host. Experimental details Crystal growth Pure crystal of K2SO4 was grown using aqueous solution by slow evaporation technique (at room temperature) .Saturated solution was prepared from synthesized K2SO4 salt ,with 2 Molar using a double distilled water as solvent . This solution was continuously stirred for about (6)hour with magnetic stirrer with rate of 250 rpm at room temperature. Finally thus solution is heated at 70 C° in order to obtain a complete dissolved of the materials. The growth process was performed in a multi-jar crystallizer to ensure identical growth conditions. In a period of 60 days, we were able to grow colorless, transparent K2SO4 single crystals which is shown in Figure(1a). Dopant crystal of K2SO4:Cu and K2SO4:Fe crystals were grown by slow evaporation technique, from 2M solutions containing 5 wt% of CuSO4.5H2O and FeSO4.7H2O respectively. The growth rate crystals was much higher than of pure K2SO4 (i.e)the growth period is about ~20 days , we get the grown crystal for K2SO4:Cu and K2SO4:Fe are shown in Figs. 1b, 1c respectively. Re- crystallization is carried in order to improve the grown crystal and step-up refinement its .Some crystals are picked from the growth apparatus and dissolve in double distilled water. This solution is treated in the same procedure as that mentioned above. We get crystal for K2SO4:Cuandfor K2SO4:Fe . 13 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 Instrument X-ray Diffract meter The X-ray diffraction was recorded using SHIMADZU model Japan (6000) diffractmeter with Cu-Kα radiation of wavelength (λ= 1.54056 Å ).The filament current and operating voltage were kept at 30mA and 40KV respectively. Thermal Analysis Differential scanning calorimetric technique (DSC) were carried out using LINSEIS model Germen(STA PT-1000).Sample of (25 mg) is used with reference of AL2O3 crucibles .Heating and cooling runs with rate of 5ºC /min during recorded of the chart. Results and Discussion The grown crystal We were able to grow colorless, transparent K2SO4 single crystals with dimensions of( 10x4x2)mm3 is shown in Figure(2a) , and the grown crystal of dimensions (11x9x4 )mm3 for K2SO4:Cu & (10x 8x5)mm3 for K2SO4:Fe are shown in Figs. 2b, 2c respectively. XRD Diffraction studies The structure of the grown crystal was studied by powder X-ray diffraction method .The recorded diffraction pattern of pure K2SO4 and doping crystals by Cu &Fe respectively, are shown in the figure(3a ,3b and 3c ).From the XRD pattern, the lattice parameter value of potassium sulfate crystal was found to be (a=7.4796 Å, b=10.0793 Å, c=5.7721 Å, α=90,β=90°, ɣ=90°) .This indicates that potassium sulfate crystallizes in orthorhombic system. The diffraction planes are indexed with the help of the computer program, with the Rietveldt refinement using FULLPROF as shown in Fig. 3a. The lattice parameters from powder XRD of the grown crystal and also unit cell dimension of pure K2SO4.The results are in agreement with reported values [3] .comparison of lattice parameters is shown in table -1- Differential scanning calorimetric (DSC) analyzes A heating rate of 5ºC /min was recorded for the grown pure samples(K2SO4) in the same chart as shown in Fig. 4.The weight of the sample taken for investigation was 22.2 mg .Which shows an endothermic peak around 300C˚(onset point 298 C˚ with reaction point -8.070µV at 298.4C˚and offset 301.2 C˚ with peak maximum -16.497µV at 300.5 C˚ and area -12.14µV S/mg) which gives a strong support to the newly detected phase transition. As the heating is continuous ,another an endothermic peak around582 C˚(onset 578.6 C˚ with reaction point -1.759µV at 580.9 C˚ and offset 584.3 C˚ with peak maximum -3.452µV at 582.6 C˚ and area -9.73µV S/mg) and when were cooling there is an exothermic peak around at≈581 C˚ (onset point 580.9 C˚ with reaction point 2.531 µV at 580.3 C˚ and offset 572.6 C˚ with peak maximum 5.088µV at 577.7 C˚ and area 10.73µV S/mg. This refers to crystallization at this region and detected a phase transition. This phase transition of the crystal have hexagonal structure at high temperature≈583C˚is known as α-K2SO4and the orthorhombic phase as of the crystal is known as β-K2SO4 at room temperature [4]. B-Doping with Cu ions A heating rate of 5ºC /min was recorded for the grown samples(5wt.%Cu.K2SO4) in the same chart as shown in Fig. 4b.The weight of the sample taken for investigation was18.94 mg .Which shows an endothermic peak around 300C˚(onset point 298 C˚ with reaction point -10.183µV at 298.4C˚and offset 301.6 C˚ with peak maximum -18.563µV at 300.8 C˚ and area -16.06 µV S/mg) which gives a strong support to the newly detected phase transition. As the heating is continuous, another endothermic peak around 585 C˚(onset 577.8 C˚ with reaction point -4.170µV at 580.5 C˚ and offset 584.3 C˚ with peak maximum -5.122 14 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 µV at 582.3 C˚ and area -9.98 µV S/mg) and when were cooling there is an exothermic peak around at≈581 C˚ (onset point 581.2 C˚ with reaction point -1.775 µV at 580. C˚ and offset 570.4 C˚ with peak maximum -0.5711 µV at 577.8 C˚ and area 11.91 µV S/mg. This refers to crystallization at this region. C- Doping with Fe ions A heating rate of 5ºC /min was recorded for the grown samples(5wt.% Fe.K2SO4) in the same chart as shown in Fig. 4c.The weight of the sample taken for investigation was 20.63mg .which shows an endothermic peak around 300C˚(onset point 298 C˚ with reaction point -12.347µV at 298.4C˚and offset 301.5 C˚ with peak maximum -20.796µV at 300.7C˚ and area -13.93µV S/mg) which gives a strong support to the newly detected phase transition. As the heating is continuous, another an endothermic peak around582 C˚(onset 577.9 C˚ with reaction point -6.887 µV at 580.8 C˚ and offset 583.7 C˚ with peak maximum -7.666µV at 581.9 C˚ and area -10.26µV S/mg) and when were cooling there is an exothermic peak around at≈581 C˚ (onset point 581.2 C˚ with reaction point -3.621 µV at 580.2 C˚ and offset 571.0 C˚ with peak maximum -2.099 µV at 577.9 C˚ and area 12.04 µV S/mg. This refers to crystallization at this region. Conclusion Colorless and transparent crystals of pure potassium sulfate were grown using water as the solvent at ambient temperature. The slow evaporation at room temperature of the solvent yielded good quality crystals. Single crystal of K2SO4was transparent colorless. Orthorhombic structure and unit cell parameter values match very well with the reported XRD standard data values. at room temperature K2SO4 pure and doping crystals having Orthorhombic structure and transition into hexagonal structure at high temperature ≈583C˚. It is supported by DSC study. References 1.Suresh Keda Bachhav, Padmakar Arjun Savale and Suresh Trimbak Pawar ,( 2010), Growth and study of BaTr single crystals by Gel Technique ,Pelagia Research Library ,1 (1) :26-33 Jalgaon (MS) India. 2.Thenmozhi, R. and Claude, A. (2012) , Rapid crystal growth of benzophenone by low temperature Solution Growth and its Characterization ,  Scholars Research Library , , 4,(2) 898-905) , ISSN 0975-508X CODEN (USA). 3. McGinnety, J.A. (1972 ) , ActaCrystallogr. B 28, 2845 (basis for PDF 01-070-1488) 4. Dammak, M. H., Khemakhem ; Zouari N. ; Mhiri T. and Kolsi A. W. , (2000), Electrical properties of ferroelectric addition compound K2SeO4.Te(OH) 6 , Solid State Ion. 127, 125. 5. Guillot Gauthier ,S. ; Peuzin, J. C. ; Olivier, M. and Rolland, G. (1984), Ferroelectrics 52, 293. 6. Khemakhem, H. (1999), Dielectric and Raman investigations on M-2(SO4).Te(OH) 6 (M= K, Rb and Cs) , Ferroelectrics 234, 47. 7. Andriyevsky, B. ; Romanyuk, M. and Stadnyk ,V. (2009) , Simulation of elastic-and- optical properties of K2SO4 crystals , Journal of Physics and Chemistry of Solids , 70(7) 1109-1112. 8.Bin Anooz, S. ; Klimm ,D. ; M. Schmidbauer and Bertram, R. (2008) , Effect of Cd2+ on the Growth and Thermal Properties of K2SO4 crystal ,  Journal of Physics and Chemistry of Solids 69 , 2356-2359 . 15 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 Table No.(1)Reported the lattice parameter of pure and dopant Present work PDF 01-070-1488 Reported data [3] parameters :Fe4SO2K :Cu4SO2K 4SO2K 9.638 8.045 3.271 90 90 90 253.6 9. 687 14. 926 9.125 90 90 90 1319.3 7.479 10.079 5.772 90 90 90 435 7.476 10.071 5.763 90 90 90 433 a (Å) b(Å) c (Å) α (°) β (°) ɣ (°) )3V(mm 16 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 4SO2pure crystal of K :Figure No. (1a) :Cu4SO2Photograph of K :Figure No. (1b) 17 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 :Fe4SO2Photograph of K :No. (1c)Figure 4SO2crystallization of crystal pure K-Re :Figure No. (2a) Figure No.(2b): Re-crystallization of crystal (2c): Re-crystallization of crystal :Fe4SO2:Cu K4SO2K 18 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 ray diffraction pattern from crushed single crystal of -Refinement the X :Figure No.(3a) 4SO2K 19 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 4SO2powder XRD pattern of pureK :Figure No. (3b) crystal 4SO25wt.%Cu.K 20 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 4SO2XRD pattern of pure K :Figure No. (3c) crystal 4SO25wt.% .Fe.K 21 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 4 SO2Figure No. (4a) DSC curve for pure crystal of K 4 SO2DSC curve for crystal doping 5wt.%Cu. K :Figure No. (4b) 22 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 4 SO2DSC curve for crystal doping 5wt.%Fe. K :Figure No. (4c) 23 | Physics 2015) عام 1(العدد 28المجلد مجلة إبن الھيثم للعلوم الصرفة و التطبيقية Ibn Al-Haitham J. for Pure & Appl. Sci. Vol. 28 (1) 2015 4SO2Kخصائص بلورة كبريتات البوتاسيوم فياثر التطعيم طارق عبد الرضا الظاھر المھداويمريم عيسى معة بغدادا/ج للعلوم الصرفة (ابن الھيثم ) قسم الفيزياء/كلية التربية 2014ايلول 15:في قبل 2014حزيران 22في :استلم الخالصة طة تقنية التبخر امن المحلول المائي بوس 2Fe+و 2Cu+نماء بلورات أحادية لكبريتات البوتاسيوم النقية والمشوبة ب & Cuللبلورات المشوبة ب 310x 8x 5 ) mm ( 3mm (11x9x 4 ). وبأبعاد في درجة حرارة الغرفة البطيء Feتغيرت أبعاد خلية الوحدة لكبريتات , إذ النماء البلوري والخصائص التركيبية في على التوالي.ودراسة اثر التطعيم Å (a=9.687 ,, للنقية والمشوبة , c=5.772 Å)(a=7.479 Å ,b=10.079 Å البوتاسيوم المطعمة بالنحاس والحديد. ) Å ,c=3.271 Å , b= 8.045 Å . (a=9.638 ,c= 9.125 Å b=14.926 تم الحصول على تحليل بنية البلورات إن التركيب البلوري لھذه XRDمقياس حيود األشعة السينية للمسحوق و استخدام تصفية ريتفيلد. أظھرت قياسات ساطةبو . )orthorhombicمعيني متعامد المحاور( البلورات ھو , حيود األشعة السينية, تصفية ريتفيلد . 2Fe ,+2Cu+: نماء بلورات ,كبريتات البوتاسيوم ,التطعيم , المفتاحية الكلمات