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ISSN: 2056-9890

(E,E)-1,2-Bis(2,4,6-trimeth­­oxy­benzyl­­idene)hydrazine

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bDepartment of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand, and cCrystal Materials Research Unit, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand
*Correspondence e-mail: hkfun@usm.my

(Received 8 August 2010; accepted 20 August 2010; online 25 August 2010)

The title mol­ecule, C20H24N2O6, lies on an inversion centre. All non-H atoms are essentially coplanar, with an r.m.s. deviation of 0.0415 (1) Å and a maximum deviation of 0.1476 (1) Å for the meth­oxy C atom at the 4-position of the benzene ring. The crystal structure is stabilized by weak C—H⋯N and C—H⋯π inter­actions.

Related literature

For standard bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For related structures, see: Jansrisewangwong et al. (2010[Jansrisewangwong, P., Chantrapromma, S. & Fun, H.-K. (2010). Acta Cryst. E66, o2170.]); Zhao et al. (2006[Zhao, Z., Feng, F., Guo, G. & Wang, W. (2006). Acta Cryst. E62, o2413-o2414.]). For background and the biological activity of hydro­zones, see: El-Tabl et al. (2008[El-Tabl, A. S., El-Saied, F. A., Plass, W. & Al-Hakimi, A. N. (2008). Spectrochim. Acta Part A, 71, 90-99.]); Qin et al. (2009[Qin, D.-D., Yang, Z.-Y. & Qi, G.-F. (2009). Spectrochim. Acta Part A, 74, 415-420.]); Ramamohan et al. (1995[Ramamohan, L., Shikkaragol, R. K., Angadi, S. D. & Kulkarni, V. H. (1995). Asian J. Pure Appl. Chem. 1, 86.]); Rollas & Küçükgüzel (2007[Rollas, S. & Küçükgüzel, Ş. G. (2007). Molecules, 12, 1910-1939.]). For the stability of the temperature controller used in the data collection, see Cosier & Glazer, (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C20H24N2O6

  • Mr = 388.41

  • Triclinic, [P \overline 1]

  • a = 7.3851 (2) Å

  • b = 7.4043 (2) Å

  • c = 9.5440 (2) Å

  • α = 71.412 (1)°

  • β = 78.095 (1)°

  • γ = 79.449 (1)°

  • V = 480.13 (2) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 100 K

  • 0.29 × 0.14 × 0.08 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.972, Tmax = 0.992

  • 11100 measured reflections

  • 2791 independent reflections

  • 2244 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.115

  • S = 1.03

  • 2791 reflections

  • 134 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.42 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C1–C6 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10B⋯N1i 0.96 2.49 3.3876 (15) 155
C8—H8CCgii 0.97 2.79 3.6678 (13) 152
C10—H10CCgiii 0.97 2.63 3.4385 (13) 142
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) -x+1, -y+2, -z; (iii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Hydrazones and their complexes are interesting due to their fluorescence properties (Qin et al., 2009) and various biological activities such as insecticidal, antitumor, antioxidant, antifungal, antibacterial and antiviral properties (El-Tabl et al., 2008; Ramamohan et al., 1995; Rollas & Küçükgüzel, 2007). These interesting properties led us to synthesize the title hydrazone derivative (I) in order to study its antibacterial activity and fluorescence property. Experiments show that (I) does not possess antibacterial activities, however it does exhibit fluorescence with the maximum emission at 410 nm when the compound is excited at 280 nm. Herein the crystal structure of (I) is reported.

The asymmetric unit of (I), (Fig. 1), C20H24N2O6, contains one half-molecule and the complete molecule is generated by an inversion centre (symmetry code -x, 2-y, 1-z). The mean plane through the C=N-N=C bridge forms a dihedral angle of 4.96 (9)° with the benzene rings. The methoxy groups attached to atoms C1 and C5 (positions 2 and 6) are approximately coplanar with the benzene ring whereas the one attached to atom C3 (position 4) is slightly twisted with respect to the benzene ring as described by the torsion angles of C8–O1–C1–C2 = 2.86 (15)°, C10–O3–C5–C4 = 3.58 (14)° and C9–O2–C3–C4 = 8.39 (15)°, respectively. The N-N bond length, 1.4117 (18) Å is comparable with 1.419 (3) Å and the C=N-N angle = 110.7 (2)°, is almost similar to 112.2 (2)° observed in (E,E)-1,2-bis(3,4,5-trimethoxybenzylidene)hydrazine (Zhao et al., 2006). The bond distances have normal values (Allen et al., 1987) and are comparable with related structures (Jansrisewangwong et al., 2010; Zhao et al., 2006). The crystal structure is stabilized by weak C—H···N and C—H···π interactions (Fig. 2).

Related literature top

For standard bond-length data, see: Allen et al. (1987). For related structures, see: Jansrisewangwong et al. (2010); Zhao et al. (2006). For background and the biological activity of hydrozones, see: El-Tabl et al. (2008); Qin et al. (2009); Ramamohan et al. (1995); Rollas & Küçükgüzel (2007). For the stability of the temperature controller used in the data collection, see Cosier & Glazer, (1986).

Experimental top

The title compound was synthesized by mixing a solution (1:2 molar ratio) of hydrazine hydrate (0.097 ml, 2 mmol) and 2,4,6-trimethoxybenzaldehyde (0.785 mg, 4 mmol) in ethanol (20 ml). The resulting solution was refluxed for 5 h, yielding the yellow solid. The resultant solid was filtered off and washed with methanol. Yellow block-shaped single crystals of the title compound suitable for x-ray structure determination were recrystalized from acetone by slow evaporation of the solvent at room temperature over several days, mp. 484–486 K.

Refinement top

The H atom attached to C7 was located in a difference map and refined isotropically. The remaining H atoms were positioned geometrically and allowed to ride on their parent atoms, with d(C—H) = 0.93 Å for aromatic and 0.96 Å for CH3 atoms. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups.

Structure description top

Hydrazones and their complexes are interesting due to their fluorescence properties (Qin et al., 2009) and various biological activities such as insecticidal, antitumor, antioxidant, antifungal, antibacterial and antiviral properties (El-Tabl et al., 2008; Ramamohan et al., 1995; Rollas & Küçükgüzel, 2007). These interesting properties led us to synthesize the title hydrazone derivative (I) in order to study its antibacterial activity and fluorescence property. Experiments show that (I) does not possess antibacterial activities, however it does exhibit fluorescence with the maximum emission at 410 nm when the compound is excited at 280 nm. Herein the crystal structure of (I) is reported.

The asymmetric unit of (I), (Fig. 1), C20H24N2O6, contains one half-molecule and the complete molecule is generated by an inversion centre (symmetry code -x, 2-y, 1-z). The mean plane through the C=N-N=C bridge forms a dihedral angle of 4.96 (9)° with the benzene rings. The methoxy groups attached to atoms C1 and C5 (positions 2 and 6) are approximately coplanar with the benzene ring whereas the one attached to atom C3 (position 4) is slightly twisted with respect to the benzene ring as described by the torsion angles of C8–O1–C1–C2 = 2.86 (15)°, C10–O3–C5–C4 = 3.58 (14)° and C9–O2–C3–C4 = 8.39 (15)°, respectively. The N-N bond length, 1.4117 (18) Å is comparable with 1.419 (3) Å and the C=N-N angle = 110.7 (2)°, is almost similar to 112.2 (2)° observed in (E,E)-1,2-bis(3,4,5-trimethoxybenzylidene)hydrazine (Zhao et al., 2006). The bond distances have normal values (Allen et al., 1987) and are comparable with related structures (Jansrisewangwong et al., 2010; Zhao et al., 2006). The crystal structure is stabilized by weak C—H···N and C—H···π interactions (Fig. 2).

For standard bond-length data, see: Allen et al. (1987). For related structures, see: Jansrisewangwong et al. (2010); Zhao et al. (2006). For background and the biological activity of hydrozones, see: El-Tabl et al. (2008); Qin et al. (2009); Ramamohan et al. (1995); Rollas & Küçükgüzel (2007). For the stability of the temperature controller used in the data collection, see Cosier & Glazer, (1986).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Atoms with suffix A were generated by symmetry code -x, 2 - y, 1 - z.
[Figure 2] Fig. 2. Part of the crystal structure showing weak hydrogen bonds as dashed lines.
(E,E)-1,2-Bis(2,4,6-trimethoxybenzylidene)hydrazine top
Crystal data top
C20H24N2O6Z = 1
Mr = 388.41F(000) = 206
Triclinic, P1Dx = 1.343 Mg m3
Hall symbol: -P 1Melting point = 484–486 K
a = 7.3851 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 7.4043 (2) ÅCell parameters from 2791 reflections
c = 9.5440 (2) Åθ = 2.3–30.0°
α = 71.412 (1)°µ = 0.10 mm1
β = 78.095 (1)°T = 100 K
γ = 79.449 (1)°Block, yellow
V = 480.13 (2) Å30.29 × 0.14 × 0.08 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2791 independent reflections
Radiation source: sealed tube2244 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
φ and ω scansθmax = 30.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1010
Tmin = 0.972, Tmax = 0.992k = 1010
11100 measured reflectionsl = 1313
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0603P)2 + 0.1087P]
where P = (Fo2 + 2Fc2)/3
2791 reflections(Δ/σ)max = 0.001
134 parametersΔρmax = 0.42 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C20H24N2O6γ = 79.449 (1)°
Mr = 388.41V = 480.13 (2) Å3
Triclinic, P1Z = 1
a = 7.3851 (2) ÅMo Kα radiation
b = 7.4043 (2) ŵ = 0.10 mm1
c = 9.5440 (2) ÅT = 100 K
α = 71.412 (1)°0.29 × 0.14 × 0.08 mm
β = 78.095 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2791 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
2244 reflections with I > 2σ(I)
Tmin = 0.972, Tmax = 0.992Rint = 0.025
11100 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.115H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.42 e Å3
2791 reflectionsΔρmin = 0.23 e Å3
134 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 120.0 (1) K.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.20858 (11)0.87907 (11)0.08848 (8)0.01756 (18)
O20.82788 (11)0.57545 (11)0.12544 (8)0.01906 (19)
O30.44058 (10)0.78425 (11)0.53298 (8)0.01517 (17)
N10.09376 (12)0.95751 (13)0.49155 (10)0.0163 (2)
C10.35619 (14)0.81164 (14)0.16438 (11)0.0142 (2)
C20.52565 (15)0.72803 (15)0.10450 (11)0.0158 (2)
H2A0.54430.71780.00780.019*
C30.66759 (14)0.65957 (15)0.19168 (11)0.0148 (2)
C40.64415 (14)0.67699 (14)0.33540 (11)0.0143 (2)
H4A0.74060.63180.39170.017*
C50.47341 (14)0.76345 (14)0.39383 (10)0.0133 (2)
C60.32381 (14)0.83151 (14)0.31125 (11)0.0134 (2)
C70.14037 (15)0.91807 (15)0.36584 (11)0.0147 (2)
C80.22823 (17)0.85390 (17)0.05710 (12)0.0205 (2)
H8A0.11270.90080.09540.031*
H8B0.26010.71990.04990.031*
H8C0.32510.92410.12340.031*
C90.96932 (16)0.47848 (17)0.21582 (12)0.0212 (2)
H9A1.06970.41730.15850.032*
H9B0.91730.38340.30220.032*
H9C1.01570.56980.24730.032*
C100.59168 (15)0.72427 (16)0.61730 (11)0.0167 (2)
H10A0.55160.74950.71230.025*
H10B0.69450.79390.56310.025*
H10C0.63020.58920.63300.025*
H70.0407 (19)0.9430 (19)0.3064 (15)0.022 (3)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0168 (4)0.0235 (4)0.0134 (3)0.0022 (3)0.0047 (3)0.0080 (3)
O20.0149 (4)0.0236 (4)0.0163 (4)0.0049 (3)0.0002 (3)0.0082 (3)
O30.0145 (4)0.0196 (4)0.0124 (3)0.0013 (3)0.0034 (3)0.0073 (3)
N10.0125 (4)0.0186 (4)0.0173 (4)0.0003 (3)0.0004 (3)0.0069 (3)
C10.0156 (5)0.0131 (4)0.0133 (4)0.0010 (4)0.0031 (4)0.0032 (4)
C20.0175 (5)0.0173 (5)0.0122 (4)0.0009 (4)0.0001 (4)0.0058 (4)
C30.0134 (5)0.0145 (5)0.0150 (4)0.0007 (4)0.0012 (4)0.0049 (4)
C40.0133 (5)0.0149 (5)0.0144 (4)0.0008 (4)0.0028 (4)0.0043 (4)
C50.0153 (5)0.0120 (4)0.0123 (4)0.0028 (4)0.0003 (4)0.0040 (3)
C60.0140 (5)0.0134 (4)0.0126 (4)0.0010 (4)0.0014 (3)0.0046 (4)
C70.0137 (5)0.0151 (5)0.0151 (4)0.0006 (4)0.0027 (4)0.0049 (4)
C80.0240 (6)0.0251 (6)0.0143 (5)0.0020 (4)0.0061 (4)0.0093 (4)
C90.0159 (5)0.0242 (5)0.0198 (5)0.0043 (4)0.0014 (4)0.0061 (4)
C100.0157 (5)0.0207 (5)0.0157 (4)0.0010 (4)0.0051 (4)0.0071 (4)
Geometric parameters (Å, º) top
O1—C11.3632 (12)C4—H4A0.9300
O1—C81.4347 (12)C5—C61.4135 (14)
O2—C31.3642 (12)C6—C71.4564 (14)
O2—C91.4328 (13)C7—H70.976 (14)
O3—C51.3528 (11)C8—H8A0.9600
O3—C101.4322 (12)C8—H8B0.9600
N1—C71.2882 (13)C8—H8C0.9600
N1—N1i1.4117 (18)C9—H9A0.9600
C1—C21.3866 (14)C9—H9B0.9600
C1—C61.4226 (13)C9—H9C0.9600
C2—C31.3944 (15)C10—H10A0.9600
C2—H2A0.9300C10—H10B0.9600
C3—C41.3909 (13)C10—H10C0.9600
C4—C51.3974 (14)
C1—O1—C8118.01 (8)N1—C7—C6125.41 (9)
C3—O2—C9117.79 (8)N1—C7—H7115.8 (8)
C5—O3—C10117.61 (8)C6—C7—H7118.7 (8)
C7—N1—N1i110.66 (11)O1—C8—H8A109.5
O1—C1—C2122.94 (9)O1—C8—H8B109.5
O1—C1—C6115.10 (9)H8A—C8—H8B109.5
C2—C1—C6121.95 (9)O1—C8—H8C109.5
C1—C2—C3118.90 (9)H8A—C8—H8C109.5
C1—C2—H2A120.5H8B—C8—H8C109.5
C3—C2—H2A120.5O2—C9—H9A109.5
O2—C3—C4123.44 (9)O2—C9—H9B109.5
O2—C3—C2115.02 (9)H9A—C9—H9B109.5
C4—C3—C2121.55 (9)O2—C9—H9C109.5
C3—C4—C5118.99 (9)H9A—C9—H9C109.5
C3—C4—H4A120.5H9B—C9—H9C109.5
C5—C4—H4A120.5O3—C10—H10A109.5
O3—C5—C4122.15 (9)O3—C10—H10B109.5
O3—C5—C6116.17 (9)H10A—C10—H10B109.5
C4—C5—C6121.67 (9)O3—C10—H10C109.5
C5—C6—C1116.93 (9)H10A—C10—H10C109.5
C5—C6—C7124.92 (9)H10B—C10—H10C109.5
C1—C6—C7118.15 (9)
C8—O1—C1—C22.86 (15)C3—C4—C5—C60.69 (15)
C8—O1—C1—C6176.61 (9)O3—C5—C6—C1179.70 (8)
O1—C1—C2—C3178.70 (9)C4—C5—C6—C11.27 (15)
C6—C1—C2—C30.74 (16)O3—C5—C6—C70.86 (15)
C9—O2—C3—C48.39 (15)C4—C5—C6—C7178.16 (9)
C9—O2—C3—C2171.46 (9)O1—C1—C6—C5179.97 (8)
C1—C2—C3—O2178.49 (9)C2—C1—C6—C50.55 (15)
C1—C2—C3—C41.37 (16)O1—C1—C6—C70.55 (14)
O2—C3—C4—C5179.18 (9)C2—C1—C6—C7178.93 (9)
C2—C3—C4—C50.67 (16)N1i—N1—C7—C6179.28 (10)
C10—O3—C5—C43.58 (14)C5—C6—C7—N15.52 (17)
C10—O3—C5—C6177.40 (8)C1—C6—C7—N1175.05 (10)
C3—C4—C5—O3179.66 (9)
Symmetry code: (i) x, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
C7—H7···O10.977 (14)2.332 (14)2.6886 (12)100.6 (10)
C10—H10B···N1ii0.962.493.3876 (15)155
C8—H8C···Cgiii0.972.793.6678 (13)152
C10—H10C···Cgiv0.972.633.4385 (13)142
Symmetry codes: (ii) x+1, y+2, z+1; (iii) x+1, y+2, z; (iv) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC20H24N2O6
Mr388.41
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)7.3851 (2), 7.4043 (2), 9.5440 (2)
α, β, γ (°)71.412 (1), 78.095 (1), 79.449 (1)
V3)480.13 (2)
Z1
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.29 × 0.14 × 0.08
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.972, 0.992
No. of measured, independent and
observed [I > 2σ(I)] reflections
11100, 2791, 2244
Rint0.025
(sin θ/λ)max1)0.703
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.115, 1.03
No. of reflections2791
No. of parameters134
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.42, 0.23

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
C10—H10B···N1i0.962.493.3876 (15)155
C8—H8C···Cgii0.972.793.6678 (13)152
C10—H10C···Cgiii0.972.633.4385 (13)142
Symmetry codes: (i) x+1, y+2, z+1; (ii) x+1, y+2, z; (iii) x+1, y+1, z+1.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

§Additional correspondence author, e-mail: suchada.c@psu.ac.th. Thomson Reuters ResearcherID: A-5085-2009.

Acknowledgements

PJ thanks the Center of Excellence for Innovation in Chemistry (PERCH-CIC), the Commission on Higher Education, Ministry of Education and the Graduate School, Prince of Songkla University, for financial support. The authors thank the Prince of Songkla University for financial support through the Crystal Materials Research Unit (CMRU) and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012.

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