Journal of Minerals & Materials Characterization & Engineering, Vol. 7, No.3, pp 215-231, 2008
jmmce.org Printed in the USA. All rights reserved
215
Growth of Strontium Chromium Magnesium Hydrogen Phosphate
(SrCrMHP) Crystal in Silica Gel Medium at Different Growth
Environments and Nucleation Reduction Strategy
G. Kanchana
1
, P. Suresh
2
, P. Sundaramoorthi
2
*, S. Kalainathan
3
, G.P. Jeyanthi
1
1
Department of Bio-chemistry, Avinashilingam Deemed University,Coimbatore,
TamilNadu, India.
2
Department of Physics, A.A.Govt. Arts College, Namakkal – India-637001.
3
Department of Physics, SSH, VIT University, Vellore - India
ABSTRACT
Kidney stone consists of various organic, inorganic and semi organic compounds.
Mineral oxalate monohydrate and di-hydrate are the main inorganic constituents of kidney
stones. However, mechanisms leading to the formation of mineral oxalate kidney stones are
not clearly understood. In this field of study, there are several hypotheses including
nucleation, crystal growth and/or aggregation of formation of AOMH (Ammonium oxalate
monohydrate) and AODH (Ammonium oxalate di-hydrate) crystals. The effect of some
urinary species such as ammonium oxalate, calcium citrate, proteins and trace elements were
reported by the author. The kidney stone constituents are grown in silica gel medium (SMS)
which provides the necessary growth simulation (in-vivo). In the artificial urinary stone
growth process, identification of growth parameters within the different chemical
environment was carried out and reported for the urinary crystals such as CHP, SHP, BHP
and MHP. In the present study, SrCrMHP (Strontium chromium magnesium hydrogen
phosphate) crystals are grown in three different growth faces to attain the total nucleation
reduction. Extension of this research, many characterization studies have been carried out
and the results are reported.
Key words: CHP, MHP, AMHP, SHP, SrCrMHP, trace element, major minerals,
minor minerals.

216 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
1. INTRODUCTION
SHP (Strontium hydrogen phosphate), CHP (Calcium hydrogen phosphate) and BHP
(Barium hydrogen phosphate) were grown in silica gel medium at room temperature. The
next approach is to grow mixed crystal in silica gel medium at different environments, which
contains one major element (Phosphate), two minor or trace elements (Strontium, Chromium)
and one inhibitor (Magnesium). SrCrMHP is a mixed crystal, which typically represent the
biological crystals formed in the human urinary tracts called renal stones. One can obtain the
periodic precipitation of Liesegang rings of biological crystal named as Brushite, Struvite,
HAP, BMHP and SMHP [1-9].
2. EXPERIMENTAL PROCEDURES
The dissociation of orthophosphoric acid system can be represented by three dissociation
equilibrium and the presence of various ions at various pH values is studied. Based on these
results, gel medium of pH in the range from 6 to 10 has been used in which the HPO
42-
ions
dominates or alone exist. This decreases the possibility of SrCrMP crystals occurring during the
SrCrMHP growth. The crystallization apparatus employed were glass test tubes of 25 mm
diameter and 150 mm length for single diffusion process (SDP) and thick walled glass U tubes
of 30 mm diameter and 180 mm length for double diffusion process (DDP). The chemicals used
were EXCELAR-Qualigens (E-Q) AR grade CrCl
2
, SrCl
2
, Mg (NO
3
)
2
.2H
2
O (MW-258.41) and
orthophosphoric acid (Sp.gr.1.75). The SMS gel or water glass was prepared as per the
literature. One of the reactants orthophosphoric acid was mixed with silica gel at desired gel
density and elevated temperatures. After the gel set, the supernatant mixture (Chromium
chloride +Strontium chloride + Magnesium nitrate) at a required mole solutions was slowly
added along the walls of the growth columns (test tubes, U-tubes) over the set gels and tightly
closed to prevent evaporation. Then the growth systems were allowed to react within the gel
medium and the following chemical reaction takes place [10-14].
(CrCl
2
+Mg (NO
3
)
2
.2H
2
O) + SrCl
2
+ H
3
PO
4
 SrCrMgHPO
4
+ Waste.
Table-1 and Table-2 represent the growth parameters of SrCrMHP crystal and the bold letters
represent the optimum growth parameters in SDP and DDP growth processes. The growth
column of different growth environments are shown in Fig 1-6.

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 217
TABLE-1.
Growth parameters of SrCrMHP crystal (SDP)
Gel
density
g /cc
Orthophosphoric
acid
concentration
Gel + H3PO4
pH
value
Gel setting time Supernatant
concentration
SrCl2+CrCl2+
Mg(NO3)2.2H2O
(1M)
Nucleation observed
in hrs
Growth
period
in
days
Types of
crystal
observed &harvested
crystal size.
1.04
1N
6.4
6.8
6.9
7.3
26 hrs
16 hrs
6 mints.
18 hrs
1:1
-do-
-do-
-do-
16 hrs
17 hrs
32 hrs
89 hrs
80
Dendrite crystals
Leaf like crystals
Single,
Poly crystals
( 3 mm x 3 mm x
3 mm )
1.5N
6.6
6.9
7.1
8.0
28 hrs
1 hrs
3 hrs
46 hrs
-do-
-do-
-do-
-do-
26 hrs
16 hrs
46 hrs
66 hrs
90
1.05
1 N
6.3
6.8
6.9
7.4
34 hrs
6 hrs
45 min
68 hrs
-do-
-do-
-do-
-do-
12 hrs
22 hrs
28 hrs
68 hrs
110
2N
6.6
6.9
7.1
7.5
24 hrs
1 hour
12 hrs
48 hrs
-do-
-do-
-do-
-do-
13 hrs
10 hrs
24 hrs
72 hrs
75

218 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
TABLE-2.
Growth parameters of SrCrMHP crystal (DDP)
Gel
density
g /cc
Orthophosphoric
acid
concentration
Gel + H3PO4
pH
value
Gel
setting time
Supernatant
concentration
SrCl2+CrCl2+
Mg(NO3)2.2H2O
(1M)
Nucleation observed
in hrs
Growth
period in
days
Types of
crystal
observed & harvested
crystal size.
1.03
1N
6.0
6.5
6.9
7.1
48 hrs
16 hrs
15 min
26 hrs
1:1
-do-
-do-
-do-
45 hrs
26 hrs
22 hrs
90 hrs
90
Dendrite crystals
Leaf like crystals
Single, poly crystals
(3 mm x
3.5 mm x 3 mm)
2N
6.4
6.9
7.2
8.1
36hrs
4 hrs
1 hrs
98 hrs
-do-
-do-
-do-
-do-
20 hrs
22 hrs
86 hrs
98 hrs
70
1.04
1 N
6.2
6.8
7.2
7.6
46 hrs
5 hrs
30 min
28 hrs
-do-
-do-
-do-
-do-
40 hrs
22 hrs
64 hrs
88 hrs
110
2N
6.2
6.9
7.5
7.9
88 hrs
1 hr
10 hrs
58 hrs
-
do
-
-do-
-do-
-do-
20 hrs
10 hrs
32 hrs
82 hrs
90

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 219
Fig-1. Growth of SrCrMHP crystal within laboratory environment (SDP).
Fig -2. Growth of SrCrMHP crystal within laboratory environment (SDP).

220 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
Fig-3. Growth of SrCrMHP crystal within sunlight exposed medium (SDP).
Fig-4. Growth of SrCrMHP crystal under laser exposed medium (SDP).

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 221
Fig-5. Harvested SrCrMHP crystals in SDP (3 mm x 3 mm x 3 mm).
Fig-6. Harvested SrCrMHP crystals in DDP (3 mm x 3.5 mm x 3 mm).

222 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
3. CHARACTERIZATION STUDIES of SrCrMHP CRYSTAL
3.1 FTIR Spectral Analysis of SrCrMHP Crystal
FTIR spectrometer having KBr pellets sample holder and KBr detector was used
for the analysis. The KBr pellet samples were used and the absorption frequencies range
from 400 to 4000 cm
-1
. Fig-7 shows the FTIR spectrum of SrCrMHP crystal. The results
matched with the reported values. The absorption bonds, absorption frequencies and
percentage of transmittance were compared with the reported values. The values are
tabulated in Table-3. The functional groups confirm the SrCrMHP crystal constituents
[15-19].
3.2 Thermo Gravimetric (TGA and DTA) Analysis of SrCrMHP Crystal
The TGA and DTA of SrCrMHP crystal was carried out by STA 11500-PLTS
instrument. SrCrMHP crystal sample of 1.290 mg was taken for TGA process. The TGA was
performed from room temperature to 1000ºC by heating it at a constant rate. Fig.-8 shows the
TGA and DTA graph of SrCrMHP crystal. The % of weight of SrCrMHP sample present at
a particular temperature is tabulated in Table-4 [20-24].
Strontium, chromium and magnesium are stable with respect to temperature up to
900 ºC. About 21.2% of SrCrMHP crystal sample was decomposed and 78.8% of the sample
remains stable.
3.3 Etching Study of SrCrMHP Crystal
A well-grown SrCrMHP crystal was immersed in HCl solution at a desired
concentration. The dissolution of SrCrMHP crystal depends upon the etchant
concentration, temperature, and crystal morphology and etching time. The etch pits are
shown in Fig-9. The etch pits observed in the photo are knife pits, cone pits, leaf pits and
step pits [25-29].

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 223
Fig-7. FTIR spectrum of SrCrMHP crystal.
FTIR Spectrum of S
r
C
r
MHP

224 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
TABLE-3
FTIR spectral analysis of SrCrMHP crystal
S.No. Vibrations/Bonds
Absorption
frequency
reported
values cm
-1
Absorption
frequency
observed
values cm
-1
% of
transmittance
1.
Sr, Cr, Mg & hydrogen
O-H Symmetric,
asymmetric (in plane)
3477 to 3047 3277.39
3516.26
19.7
22.5
2.
Out of plane O-H
bending 662-780 692.02
32.8
3.
PO
4
group 1000 to 1100
1167.26
1062.72
1022.41
21.7
19.1
18.5
4.
Sr, Cr, magnesium/
apatite groups
600-1010 (high
Frequency)
692 32.8
5.
COD (Cr oxalate
dihydrate) 517 506.90 28.1

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 225
Fig-8. Thermo gravimetric (TGA and DTA) analysis of SrCrMHP crystal.

226 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
TABLE- 4.
Thermal analysis of SrCrMHP crystal
Points
TGA
DTA
in
0
C
Temperature
(
0
C)
% of SrCrMHP
crystal
present
Quantity of
sample
remaining
(mg)
1
2
3
4
5
35
122.19
190.69
-
-
100
104.4
78.8
78.8
78.8
1.290
1.35
1.02
1.02
1.02
122.94
170.33
237.58
668.33
686.87
Fig-9. Chemical etching of SrCrMHP crystal at room temperature (1.5 mm - 40X).
3.4 Scanning Electron Microscopic Study of SrCrMHP Crystal
A well-grown SrCrMHP single crystal was selected for the investigation of
surface morphology by using SEM. The SEM photograph was taken in the version S-300-
I instrument. The sample named VCA-600 was kept in lobe middle; the data size was 640
x 480 µm. The minor and major magnification of SEM was about 250 times. SEM
accelerating voltage was 25000 volts and the sample was kept in a high vacuum at
18200 µm working distance and monochromatic colour mode was employed. 50 µm

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 227
focusing of SrCrMHP crystal SEM is shown in Fig-10. In the surface analysis of SEM-
SrCrMHP crystal, smooth, fine grain boundaries and few valley regions were observed
[30-38].
3.5 X-ray Diffraction of SrCrMHP Crystal
The single crystal XRD result reveals the crystalline nature of the grown crystal.
The lattice parameters of the SrCrMHP crystal were calculated. The lattice index data are
as follows.
CD0> LO
From to: 1 25
1H 4. -1. 3. * 11.18 S -23.94 11.56 -2.12 **S 2 0.61 771.9
2H 4. 1. 3. * 10.17 S -1.27 10.65 -2.22 **S 2 0.52 691.4
3H 3. 3. 3. * 10.30 S 20.47 8.00 6.41 **S 2 0.55 8629.2
4H 2. 4. 2. * 9.77 S 40.22 8.51 4.22 **S 2 0.63 32860.5
5H 3. -2. 3. * 9.28 S -41.65 6.78 7.84 **S 2 0.65 18929.0
6H 4. 1. 4. * 11.37 S -6.17 9.08 8.04 **S -2 0.60 2185.0
7H 4. -1. 4. * 11.39 S -26.55 8.96 8.33 **S -2 0.64 2317.0
8H 4. -2. 4. * 11.89 S -35.60 9.03 8.10 **S 2 0.68 20586.8
9H 1. 1. 5. * 9.99 S -15.66 -7.75 52.95 **S 2 0.66 479.8
10H -1. 3. 4. * 9.99 S 29.11 -11.67 62.97 **S 2 0.89 15019.5
11H 0. 2. 5. * 10.37 S 0.82 -11.46 63.06 **S 2 0.54 17371.0
12H 1. 0. 6. * 11.69 S -32.48 -7.62 57.31 **S 2 0.67 5865.0
13H 1. 2. 6. * 12.36 S -5.31 -5.73 53.01 **S 2 0.69 1626.3
14H -1. 3. 3. * 8.53 S 41.39 -10.73 56.32 **S -2 0.68 1955.6
15H 1. 0. 4. * 7.90 S -30.41 -8.75 50.74 **S -2 0.64 9272.4
16H 0. 2. 4. * 8.62 S 8.06 -11.83 59.66 **S -2 0.59 1588.7
17H 0. 0. 4. * 7.63 S -38.17 -16.89 71.56 **S -2 0.65 2069.7
18H 0. 2. 6. * 12.18 S -4.63 -10.48 65.17 **S -2 0.76 3917.2
19H -2. 4. 5. * 13.17 S 36.66 -9.78 66.59 **S 2 0.67 9668.4
20H 0. 2. 7. * 14.04 S -8.92 -9.11 66.62 **S 2 0.68 14379.1
21H -1. 3. 4. * 9.93 S 28.98 -11.52 62.95 **S 2 0.65 14779.0
22H 0. 2. 5. * 10.38 S 0.66 -11.32 63.04 **S 2 0.69 17581.7
23H 0. 2. 6. * 12.18 S -4.82 -10.34 65.17 **S -2 0.78 4242.5
24H 1. 0. 6. * 11.68 S -32.30 -7.67 57.26 **S 2 0.76 5968.1
25H 1. 2. 6. * 12.35 S -5.37 -5.66 53.00 **S 2 0.93 16833.1
CD0> REIND
Nr S H K L Dev-Ang dTh dPh dCh
0.0093629
1 H 4.009 -1.002 2.995 0.1061 -0.011 0.019 0.105
0.0010538
2 H 3.999 1.000 3.003 0.0266 -0.002 0.001 -0.027
0.0002487
3 H 2.997 2.999 3.002 0.0338 0.003 -0.003 -0.034
0.0003242
4 H 1.999 4.002 2.003 0.0273 -0.005 -0.005 -0.027
0.0003231
5 H 3.000 -2.001 3.004 0.0365 -0.006 -0.006 -0.036
0.0004269
6 H 3.998 0.999 3.995 0.0228 0.009 0.000 0.023
0.0004750
7 H 3.998 -0.998 4.000 0.0158 0.004 -0.012 -0.010
0.0002439
8 H 3.998 -1.998 4.000 0.0226 0.004 -0.014 -0.018
0.0002931

228 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
9 H 1.002 0.999 5.002 0.0261 -0.005 0.026 0.016
0.0003177
10 H -1.001 2.998 4.000 0.0267 0.001 0.000 -0.027
0.0002356
11 H 0.000 2.001 5.000 0.0125 0.000 -0.016 0.006
0.0001124
12 H 0.997 -0.001 6.005 0.0438 -0.009 0.019 -0.042
0.0006067
13 H 1.001 1.999 6.002 0.0150 -0.003 0.017 0.008
0.0002098
14 H -1.004 2.995 3.003 0.0941 0.002 0.008 -0.094
0.0006959
15 H 0.994 -0.001 4.002 0.0955 0.000 0.017 -0.096
0.0006462
16 H -0.001 1.998 3.998 0.0213 0.005 -0.006 -0.024
0.0002826
17 H -0.006 -0.001 4.000 0.0976 0.000 0.032 -0.097
0.0006389
18 H 0.004 2.000 5.995 0.0424 0.009 -0.001 0.044
0.0006076
19 H -1.998 4.002 5.001 0.0256 -0.002 0.016 0.023
0.0003099
20 H 0.003 2.002 6.997 0.0295 0.004 -0.015 0.029
0.0003975
21 H -1.001 2.999 4.000 0.0111 0.002 -0.004 -0.012
0.0001234
22 H 0.000 2.003 5.002 0.0238 -0.005 -0.028 0.014
0.0003267
23 H 0.003 2.003 5.998 0.0396 0.001 -0.020 0.037
0.0004159
24 H 1.000 -0.001 6.001 0.0082 -0.002 0.007 -0.007
0.0001302
25 H 1.002 2.000 5.998 0.0209 0.004 0.003 0.0229
0.0002846
Reciprocal axis matrix Direct axis matrix
0.019356 -0.095158 0.012389 1.934520 7.88982 -6.028681
0.077469 0.024921 0.054601 -9.932248 2.392297 -0.107989
-0.059732 -0.000905 0.075899 1.421146 6.237479 8.552554
Niggli-values Sigma direct axis matrix
100.5313 103.3842 118.0713 0.004457 0.002937 0.003931
-0.1169 -0.1434 0.0792 0.002609 0.001702 0.002302
0.003732 0.002434 0.003289
Cell parameters Sigma cell parameters
a =10.0230Å, b =10.2067Å, c =10.5844Å,
α
αα
α =90.1808˚, β
ββ
β =90.0243˚, γ
γγ
γ =90.0752˚. 0.0230 0.0256 0.0274
-0.001071 -0.001339 0.000773 0.000401 0.000449 0.000476
Volume= 1094.6399
.
0.5550
Index-Status: HHHHHHHHHHHHHHHHHHHHHHHHH
CD0>
The lattice parameters are a=10.0230Å, b=10.2067Å, c=10.5844Å, α αα α=90.1808˚,
β ββ β=90.0243˚ and γ γγ γ=90.0752˚. The volume of the unit cell of the SrCMHP crystal is
1094.6399 (Å)
3.
From this data, it is confirmed that the SrCMHP crystal system is
triclinic.

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 229
Fig-10. SEM picture of SrCrMHP crystal.
4. CONCLUSION
The crystal structures, growth morphology, chemical constituents, surface
morphology and TGA/DTA analysis of Strontium chromium magnesium hydrogen
phosphate (SrCrMHP) crystals have been investigated. The SrCrMHP crystals were
grown under three different growth conditions. The optimum growth environments have
been identified. FTIR spectrum was recorded and the functional group analysis of
SrCrMHP crystal confirms the SrCrMHP chemical constituents. Chemical etching studies
were carried out at room temperature and the etch pits are identified. The surface
morphology of the grown crystal was recorded using SEM photograph. The thermal
stabilities of the crystal were investigated by TGA/DTA analysis. XRD data confirm that
the SrCrMHP crystals belong to triclinic system.
REFERENCES
[1] C.Y.C. Pak, et al, Effects of de-posphonate on crystallization of calcium oxalate
in-vitro, Kidney.Int.7 (1975) 154-160.
[2] L.Goe, Manual of Nephrology in the patients with renal stone, W. Sckrier (4
th
edi..) Little Brous, (1981).
[3] P. Sundaramoorthi, S.Kalainathan, Growth of CaHPO
4
crystals in silica gel media
and its characterization studies, nucleation reduction process. Asian journal of
chemistry, 19 (2007) (In press)
[4] M.Menon, Compbell’s Urology- 3, New York, (1998).
SEM
-
Picture of SrC
r
MHP crystal
-
50
µm

230 G. Kanchana, P. Suresh, P. Sundaramoorthi, S. Kalainathan, G.P. Jeyanthi Vol.7, No.3
[5] S.Joshi and J.Joshi, FTIR spectroscopic, thermal and growth morphological
studies of calcium hydrogen phosphate dehydrate crystals, Cryst.Res.Technol.38,
(2003) 817-821.
[6]. P.Sundaramoorthi, S.Kalainathan, Growth and characterizations studies of SMHP
single crystal in silica gel medium and laser induced nucleation reduction
process. Biochemical Engineering Journal, 34 (2007) 244-249.
[7] P.Sundaramoorthi, S. Kalainathan, Characteristics studies of SHP crystals are
grown in silica gel medium. Asian journal of chemistry, 19 (5) (2007) 3739-3746
[8] P.Sundaramoorthi, S.Kalainathan, Crystal growth of some renal stones
constituents: I In vitro crystallization of trace element and its characterization
studies. The Journal of minerals and materials characterization of Engineering (In
press)
[9] P.Sundaramoorthi, S.Kalainathan, BMHP single crystal growth in silica gel
medium, characterization studies and laser irradiated nucleation reduction
process strategy. Asian journal of chemistry, 19 (2007) (In press)
[10] J. Dennis, Crystal growths in gels, J.Elec.Che.Soc.14 (1967) 263.
[11] J.W. Mullin, Crystallization, Butter worth scientific pub. London 4, (1961).
[12] E. Hatscheck, Light affects the crystallization nuclei. Kollid Z.37 (1925) 297.
[13] A.J Arminstrong, The scraped sell crystallizer, British chemical engineering, 14
(1969) 647-649.
[14] H.K. Henisch, J.I. Hanoka, and J. Dennis, Surface barrier effects of crystals
growth in gel medium, J.Electrochem.Soc.112 (1965) 627.
[15] G. Socrater, Infrared Cha. Group Friq, Johnwilly, Chichester, (1980).
[16] S. Matsuzaki, K. Matsushita, K. Tanykawa, A. Masuda and F. Matsunaga,
Sequential analysis of recurrent calcium calculi by infrared spectroscopy,
Int.J.Uro.2 (1995) 235-237.
[17] Yean-Chin Tsay, Application of infrared spectroscopy to analysis of urinary
calculi, J.Urol. 86 (1961) 838-854.
[18] C.M. Corns, Infrared analysis of renal calculi-a comparison with conventional
technique. J.Ann. Clin. Bio-Cherm 20 (1983) 20-35.
[19] A. Hesse and D. Bach, Stone analysis by infrared spectroscopy, In., Urinary
stones, Clinical and laboratory Aspects, Edi., Alan Rose, University Park Press,
Baltimore, (1982).
[20] P.N. Kotru, K.K. Raina and N.K Guptha, Characterizations as thermal behavior
of Lanthanum tartar ate crystals grown from gels. Bull. Mater Sci.8 (1986) 547.
[21] Anand Kumar Sharma, Shyam Kumar and Narender Kumar Kaushik, Thermall
Studies on magnesium, barium and lead, zirconyloxalates, Thermochimica
Acta, 47(1981) 149-156.
[22] G. Bruzzone, The binary systems calcium-copper, strontium-copper and barium-
copper, J. Less Common Metals, 25 (1971) 361-366.
[23] G. Bruzzone, The binary systems Sr-In and Ba-In .J. Less Common Metals, 11,
(1966) 249-258.

Vol.7, No.3 Growth of Strontium Chromium Magnesium Hydrogen Phosphate 231
[24] Sedat Ilhan, Cem Kahruman and Ibrahim Yusufoglu , Characterization of the
thermal decomposition products of ammonium phosphomolybdate hydrate, J.
Analytical and Applied Pyrolysis, 78 (2007) 363-370.
[25] J.J. Gilman, J. Johnsion and G.W. Sears , Dislocation etch pit formation in
Lithium fluoride, J.App. Physics, 295 (1958) 749.
[26] J.J. Gilman, et al, Observations Lithium fluoride dislocation glide climb in
Lithium fluoride crystals, J.App. Physics, 27 (1956) 1018.
[27] J.C. Fisher, In: Dissolutions and Mechanical Properties of Crystals, John Wiley
and sons, New York, (1957).
[28] J.B. New Kirk, In: Director Observation of Imperfection in crystals, Inter science
Publishers, New York (1962).
[29] K. Sangwal, Chemical etching principles and the present status, Key Engineering
Materials, 58 (1991) 170-187.
[30] K. Tasukamot, In situ observation of mono-molecular growth step on crystal
growth in aqueous solution-I, J. Cry. Growth, 61 (1983) 199.
[31] H.C. Gates, Thirty years of progress in Surface Science, In: Crystal growth and
characterization, Edi, North Holland, (1975).
[32] H. Bethage, et al, edi, Electron Microscopy in Solid State Physics, Elsever,
Amsterdom, (1987).
[33] N. Albon et al, In: Growth and Perfection of Crystals, Wiley., New York, (1958).
[34] H.K. Henisch, J.M. Garcia-Ruiz, Crystal growth in gels and Lisegang ring
formation, J.Crystal Growth, 75 (1986) 195.
[35] H.K. Henisch, J.M. Garcia-Ruiz, Crystal growth in gels and Lisegang ring
formation-II crystallization criteria and successive precipitation, J.Cry.Growth 75
(1986) 203.
[36] H.K. Henisch, Crystals in Gel and Liesegang Rings, Cambridge University press,
Cambridge (1986).