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The title compound, C17H12Cl2O, crystallizes in a centrosymmetric space group. The dihedral angle between the two benzene rings is 24.7 (1)°. The crystal packing is characterized by non-classical C—H...O and C—H...Cl inter- and intra­molecular hydrogen bonds.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807050696/pv2035sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536807050696/pv2035Isup2.hkl
Contains datablock I

CCDC reference: 667402

Key indicators

  • Single-crystal X-ray study
  • T = 293 K
  • Mean [sigma](C-C) = 0.003 Å
  • R factor = 0.049
  • wR factor = 0.164
  • Data-to-parameter ratio = 25.3

checkCIF/PLATON results

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Alert level C PLAT242_ALERT_2_C Check Low Ueq as Compared to Neighbors for C17 PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 1 C17 H12 Cl2 O
Alert level G PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature 293 K PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature . 293 K
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 2 ALERT level C = Check and explain 2 ALERT level G = General alerts; check 2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check

Comment top

Chalcones with the general formula Ar—CH=CH—CO—Ar are an important class of compounds, with the common structural entity being the central –CH=CH—C(=O)- group, in which the H atoms can be substituted. The –C=C– double bond can be photoreactive and can produce various products through solid-state photocycloaddition. Therefore, chalcones are widely used in organic solid-state photochemistry (Gould et al., 1995). Reviews on the bioactivities of various chalcones have been reported (Go et al., 2005). Recently, it has been noted that, among many organic compounds reported for their second harmonic generation, chalcone derivatives are known for their excellent blue light transmittance and good crystallizability (Fichou et al., 1988). They provide a necessary configuration for NLO activity, with two planar rings connected through a conjugated double bond (Indira et al., 2002). They are also inherently chiral owing to the fact that the two phenyl rings are mutually twisted with respect to the linking backbone (Butcher et al., 2006). This helicity has also been shown to lead to NLO activity (Botek et al., 2004). Bis-chalcones are also found to exhibit good NLO properties (Uchida et al., 1998). In order to obtain detailed information on the molecular conformation of the chlorophenyl-substituted chalcone (I) in the solid state, its X-ray crystal structure was determined.

The bond lengths and angles in the title compound (Fig. 1) lie whithin normal ranges (Allen et al., 1987). The enone group and the two benzene rings of the chalcone are individually planar, with a maximum deviation of -0.005 (3), -0.007 (2) 0.051 (2) Å for atoms C4, C17 and C9, from the planes C1—C6, C12—C17 and O/C7—C11, respectively. The dihedral angle between the least-squares planes of the two benzene rings is 24.7 (1)°. The least-squaes plane through the enone unit (C7—C11/O) makes dihedral angles of 15.4 (1) and 11.4 (1)° with the C1—C6 and C12—C17 benzene rings, respectively. The five-C-atom backbone shows alternating double and single bonds [C7—C8 = 1.310 (3) Å, C8—C9 = 1.463 (3) Å, C9—C10 = 1.470 (3) Å, C10—C11 = 1.322 (3) Å and C11—C12 = 1.457 (3) Å] and thus gives no indication of conjugation. The most commonly cited factors found in organic molecules possessing NLO properties are the presence of donor-acceptor substituents on a conjugated backbone. Since this molecule does not possess either of these factors the helicity of the molecule must be the origin of the observed NLO effects.

Atoms Cl1 and Cl2 deivate by 0.027 (4) and 0.022 (1) Å, respectively, from the plane of the attached benzene rings. The widening of the C11—C12—C13 angle to 121.7 (2)° and C10—C11—C12 to 126.4 (2)° can be ascribed to the short interatomic contact between atoms H13 and H10 (2.15 Å). In addition, the strain induced by the short H8—H5 (2.19 Å) contact results in a slight opening of the C5—C6—C7 angle to 121.7 (2)° and similar to those observed in other comparable structures (Ravishankar et al., 2005).

The crystal packing is characterized by non-classical C—H···O and C—H···Cl inter and intramolecular hydrogen bonds (Table 2). Atoms C8 and C16 in the molecule at (x, y, z) act as hydrogen donors to O in the molecule at (-x + 1/2, y + 1/2, z) and to O with molecule at (-x + 1, y + 1/2, -z - 1/2), respectively. The chain is formed between symmetry related molecules through C8—H8···O and C16—H16···O hydrogen bonds.

Related literature top

For related literature, see: Allen et al. (1987); Botek et al. (2004); Butcher et al. (2006); Fichou et al. (1988); Go et al. (2005); Gould et al. (1995); Indira et al. (2002); Ravishankar et al. (2005); Uchida et al. (1998)..

Experimental top

1 mol (5 ml) of acetone was taken in 50 ml me thanol and then 2 mol (25 ml) of chloro benzaldehyde was added. To this solution 50 ml of 5 mol (10 g in 50 ml water) sodium hydroxide solution was added at 273 K. This mixture was stirred over night and the product was filtered. Single crystals of the title compound suitable for X-ray diffraction were obtained by slow evaporation of a solution in ethylacetate.

Refinement top

All H atoms were fixed geometrically and allowed to ride on their parent C atoms, with C—H distances of 0.93 Å, and with Uiso(H) = 1.2Ueq(C).

Structure description top

Chalcones with the general formula Ar—CH=CH—CO—Ar are an important class of compounds, with the common structural entity being the central –CH=CH—C(=O)- group, in which the H atoms can be substituted. The –C=C– double bond can be photoreactive and can produce various products through solid-state photocycloaddition. Therefore, chalcones are widely used in organic solid-state photochemistry (Gould et al., 1995). Reviews on the bioactivities of various chalcones have been reported (Go et al., 2005). Recently, it has been noted that, among many organic compounds reported for their second harmonic generation, chalcone derivatives are known for their excellent blue light transmittance and good crystallizability (Fichou et al., 1988). They provide a necessary configuration for NLO activity, with two planar rings connected through a conjugated double bond (Indira et al., 2002). They are also inherently chiral owing to the fact that the two phenyl rings are mutually twisted with respect to the linking backbone (Butcher et al., 2006). This helicity has also been shown to lead to NLO activity (Botek et al., 2004). Bis-chalcones are also found to exhibit good NLO properties (Uchida et al., 1998). In order to obtain detailed information on the molecular conformation of the chlorophenyl-substituted chalcone (I) in the solid state, its X-ray crystal structure was determined.

The bond lengths and angles in the title compound (Fig. 1) lie whithin normal ranges (Allen et al., 1987). The enone group and the two benzene rings of the chalcone are individually planar, with a maximum deviation of -0.005 (3), -0.007 (2) 0.051 (2) Å for atoms C4, C17 and C9, from the planes C1—C6, C12—C17 and O/C7—C11, respectively. The dihedral angle between the least-squares planes of the two benzene rings is 24.7 (1)°. The least-squaes plane through the enone unit (C7—C11/O) makes dihedral angles of 15.4 (1) and 11.4 (1)° with the C1—C6 and C12—C17 benzene rings, respectively. The five-C-atom backbone shows alternating double and single bonds [C7—C8 = 1.310 (3) Å, C8—C9 = 1.463 (3) Å, C9—C10 = 1.470 (3) Å, C10—C11 = 1.322 (3) Å and C11—C12 = 1.457 (3) Å] and thus gives no indication of conjugation. The most commonly cited factors found in organic molecules possessing NLO properties are the presence of donor-acceptor substituents on a conjugated backbone. Since this molecule does not possess either of these factors the helicity of the molecule must be the origin of the observed NLO effects.

Atoms Cl1 and Cl2 deivate by 0.027 (4) and 0.022 (1) Å, respectively, from the plane of the attached benzene rings. The widening of the C11—C12—C13 angle to 121.7 (2)° and C10—C11—C12 to 126.4 (2)° can be ascribed to the short interatomic contact between atoms H13 and H10 (2.15 Å). In addition, the strain induced by the short H8—H5 (2.19 Å) contact results in a slight opening of the C5—C6—C7 angle to 121.7 (2)° and similar to those observed in other comparable structures (Ravishankar et al., 2005).

The crystal packing is characterized by non-classical C—H···O and C—H···Cl inter and intramolecular hydrogen bonds (Table 2). Atoms C8 and C16 in the molecule at (x, y, z) act as hydrogen donors to O in the molecule at (-x + 1/2, y + 1/2, z) and to O with molecule at (-x + 1, y + 1/2, -z - 1/2), respectively. The chain is formed between symmetry related molecules through C8—H8···O and C16—H16···O hydrogen bonds.

For related literature, see: Allen et al. (1987); Botek et al. (2004); Butcher et al. (2006); Fichou et al. (1988); Go et al. (2005); Gould et al. (1995); Indira et al. (2002); Ravishankar et al. (2005); Uchida et al. (1998)..

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2/SAINT (Bruker, 2004); data reduction: SAINT/XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: 'SHELXL97 (Sheldrick, 1997) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The molecular configuration and atom-numbering scheme for (I). Displacement ellipsoids are drawn at the 50% probability level.
(1E,4E)-1,5-Bis(2-chlorophenyl)penta-1,4-dien-3-one top
Crystal data top
C17H12Cl2OZ = 8
Mr = 303.17F(000) = 1248
Orthorhombic, PbcaDx = 1.355 Mg m3
Hall symbol: -P 2ac 2abMo Kα radiation, λ = 0.71073 Å
a = 14.2816 (4) ŵ = 0.43 mm1
b = 8.3056 (2) ÅT = 293 K
c = 25.0612 (7) ÅBlock, colourless
V = 2972.69 (14) Å30.28 × 0.25 × 0.22 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2450 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.038
Graphite monochromatorθmax = 30.7°, θmin = 2.2°
ω and π scansh = 1820
22033 measured reflectionsk = 1011
4611 independent reflectionsl = 3536
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.049H-atom parameters constrained
wR(F2) = 0.164 w = 1/[σ2(Fo2) + (0.0699P)2 + 0.9731P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max = 0.011
4611 reflectionsΔρmax = 0.47 e Å3
182 parametersΔρmin = 0.53 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0030 (8)
Crystal data top
C17H12Cl2OV = 2972.69 (14) Å3
Mr = 303.17Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 14.2816 (4) ŵ = 0.43 mm1
b = 8.3056 (2) ÅT = 293 K
c = 25.0612 (7) Å0.28 × 0.25 × 0.22 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2450 reflections with I > 2σ(I)
22033 measured reflectionsRint = 0.038
4611 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.164H-atom parameters constrained
S = 1.00Δρmax = 0.47 e Å3
4611 reflectionsΔρmin = 0.53 e Å3
182 parameters
Special details top

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
Cl10.19158 (5)0.33914 (8)0.05290 (3)0.0752 (2)
Cl20.53509 (5)0.68564 (13)0.27210 (4)0.1094 (4)
O0.34751 (11)0.5172 (2)0.11420 (6)0.0648 (4)
C10.12252 (15)0.5095 (3)0.04574 (8)0.0516 (5)
C20.05863 (18)0.5433 (3)0.08563 (10)0.0654 (6)
H20.05410.47650.11530.078*
C30.00218 (19)0.6754 (3)0.08120 (11)0.0707 (7)
H30.04060.69910.10810.085*
C40.00836 (18)0.7731 (3)0.03728 (11)0.0672 (6)
H40.03080.86200.03410.081*
C50.07240 (16)0.7397 (3)0.00203 (10)0.0590 (5)
H50.07640.80780.03140.071*
C60.13174 (14)0.6063 (2)0.00091 (8)0.0462 (4)
C70.20176 (14)0.5733 (2)0.04012 (8)0.0484 (5)
H70.24630.49520.03220.058*
C80.20827 (15)0.6427 (3)0.08693 (9)0.0521 (5)
H80.16180.71510.09690.063*
C90.28492 (14)0.6120 (2)0.12432 (8)0.0470 (4)
C100.28378 (15)0.7056 (3)0.17410 (8)0.0515 (5)
H100.23270.77200.18080.062*
C110.35188 (15)0.6998 (2)0.20975 (8)0.0496 (5)
H110.40150.63050.20250.059*
C120.35691 (14)0.7913 (2)0.25926 (8)0.0475 (4)
C130.28148 (18)0.8818 (3)0.27774 (9)0.0624 (6)
H130.22610.88180.25820.075*
C140.2859 (2)0.9710 (3)0.32385 (10)0.0711 (7)
H140.23411.02960.33520.085*
C150.3674 (2)0.9731 (3)0.35301 (10)0.0709 (7)
H150.37111.03430.38400.085*
C160.44293 (19)0.8857 (3)0.33661 (10)0.0703 (7)
H160.49800.88710.35640.084*
C170.43749 (16)0.7952 (3)0.29065 (9)0.0578 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0917 (5)0.0741 (4)0.0596 (4)0.0182 (3)0.0139 (3)0.0108 (3)
Cl20.0541 (4)0.1692 (9)0.1050 (7)0.0231 (5)0.0262 (4)0.0501 (6)
O0.0577 (10)0.0728 (10)0.0640 (10)0.0112 (8)0.0196 (8)0.0131 (8)
C10.0510 (12)0.0584 (11)0.0453 (11)0.0054 (9)0.0057 (9)0.0072 (8)
C20.0693 (15)0.0781 (15)0.0489 (12)0.0078 (12)0.0187 (11)0.0046 (11)
C30.0610 (14)0.0860 (17)0.0652 (16)0.0031 (13)0.0208 (13)0.0230 (13)
C40.0583 (14)0.0683 (14)0.0752 (16)0.0071 (11)0.0113 (13)0.0175 (12)
C50.0575 (13)0.0581 (12)0.0615 (13)0.0019 (10)0.0091 (11)0.0047 (10)
C60.0436 (10)0.0513 (10)0.0436 (10)0.0047 (8)0.0053 (9)0.0078 (8)
C70.0475 (11)0.0486 (10)0.0492 (11)0.0009 (8)0.0073 (9)0.0030 (8)
C80.0455 (11)0.0614 (12)0.0493 (11)0.0038 (9)0.0095 (9)0.0042 (9)
C90.0428 (11)0.0512 (10)0.0470 (11)0.0066 (9)0.0050 (9)0.0001 (8)
C100.0440 (11)0.0645 (12)0.0458 (11)0.0012 (9)0.0043 (9)0.0018 (9)
C110.0451 (11)0.0560 (11)0.0475 (11)0.0044 (9)0.0035 (9)0.0018 (8)
C120.0494 (11)0.0515 (10)0.0416 (10)0.0082 (9)0.0036 (9)0.0046 (8)
C130.0594 (14)0.0776 (14)0.0502 (12)0.0061 (12)0.0113 (11)0.0018 (10)
C140.0816 (19)0.0757 (15)0.0561 (14)0.0101 (13)0.0011 (13)0.0078 (11)
C150.093 (2)0.0719 (15)0.0474 (13)0.0124 (14)0.0050 (14)0.0074 (11)
C160.0673 (16)0.0889 (17)0.0546 (14)0.0196 (14)0.0173 (12)0.0047 (12)
C170.0487 (12)0.0711 (13)0.0538 (13)0.0100 (10)0.0068 (10)0.0015 (10)
Geometric parameters (Å, º) top
Cl1—C11.734 (2)C8—H80.9300
Cl2—C171.729 (3)C9—C101.470 (3)
O—C91.218 (2)C10—C111.322 (3)
C1—C21.382 (3)C10—H100.9300
C1—C61.387 (3)C11—C121.457 (3)
C1—Cl11.734 (2)C11—H110.9300
C2—C31.366 (4)C12—C131.393 (3)
C2—H20.9300C12—C171.394 (3)
C3—C41.370 (4)C13—C141.374 (3)
C3—H30.9300C13—H130.9300
C4—C51.373 (3)C14—C151.375 (4)
C4—H40.9300C14—H140.9300
C5—C61.397 (3)C15—C161.363 (4)
C5—H50.9300C15—H150.9300
C6—C71.460 (3)C16—C171.377 (3)
C7—C81.310 (3)C16—H160.9300
C7—H70.9300C17—Cl21.729 (3)
C8—C91.463 (3)
C2—C1—Cl1117.80 (18)C8—C9—C10116.29 (19)
C6—C1—Cl1120.16 (16)C11—C10—C9123.1 (2)
C2—C1—Cl1117.80 (18)C11—C10—H10118.4
C6—C1—Cl1120.16 (16)C9—C10—H10118.4
C3—C2—C1119.6 (2)C10—C11—C12126.4 (2)
C3—C2—H2120.2C10—C11—H11116.8
C1—C2—H2120.2C12—C11—H11116.8
C2—C3—C4120.2 (2)C13—C12—C17116.0 (2)
C2—C3—H3119.9C13—C12—C11121.77 (19)
C4—C3—H3119.9C17—C12—C11122.2 (2)
C3—C4—C5120.0 (2)C14—C13—C12122.3 (2)
C3—C4—H4120.0C14—C13—H13118.8
C5—C4—H4120.0C12—C13—H13118.8
C4—C5—C6121.8 (2)C13—C14—C15119.5 (3)
C4—C5—H5119.1C13—C14—H14120.2
C6—C5—H5119.1C15—C14—H14120.2
C1—C6—C5116.40 (19)C16—C15—C14120.2 (2)
C1—C6—C7121.79 (19)C16—C15—H15119.9
C5—C6—C7121.79 (19)C14—C15—H15119.9
C8—C7—C6126.6 (2)C15—C16—C17119.9 (2)
C8—C7—H7116.7C15—C16—H16120.1
C6—C7—H7116.7C17—C16—H16120.1
C7—C8—C9123.4 (2)C16—C17—C12122.1 (2)
C7—C8—H8118.3C16—C17—Cl2117.81 (19)
C9—C8—H8118.3C12—C17—Cl2120.11 (18)
O—C9—C8121.90 (19)C16—C17—Cl2117.81 (19)
O—C9—C10121.78 (19)C12—C17—Cl2120.11 (18)
C6—C1—C2—C30.2 (4)O—C9—C10—C113.4 (3)
Cl1—C1—C2—C3179.26 (19)C8—C9—C10—C11174.8 (2)
Cl1—C1—C2—C3179.26 (19)C9—C10—C11—C12178.49 (19)
C1—C2—C3—C40.5 (4)C10—C11—C12—C138.8 (3)
C2—C3—C4—C51.0 (4)C10—C11—C12—C17170.5 (2)
C3—C4—C5—C60.8 (4)C17—C12—C13—C140.6 (3)
C2—C1—C6—C50.4 (3)C11—C12—C13—C14178.8 (2)
Cl1—C1—C6—C5179.06 (16)C12—C13—C14—C150.4 (4)
Cl1—C1—C6—C5179.06 (16)C13—C14—C15—C160.8 (4)
C2—C1—C6—C7177.7 (2)C14—C15—C16—C170.1 (4)
Cl1—C1—C6—C72.9 (3)C15—C16—C17—C121.0 (4)
Cl1—C1—C6—C72.9 (3)C15—C16—C17—Cl2179.5 (2)
C4—C5—C6—C10.1 (3)C15—C16—C17—Cl2179.5 (2)
C4—C5—C6—C7178.2 (2)C13—C12—C17—C161.3 (3)
C1—C6—C7—C8170.1 (2)C11—C12—C17—C16178.0 (2)
C5—C6—C7—C811.9 (3)C13—C12—C17—Cl2179.23 (18)
C6—C7—C8—C9175.07 (19)C11—C12—C17—Cl21.5 (3)
C7—C8—C9—O0.9 (3)C13—C12—C17—Cl2179.23 (18)
C7—C8—C9—C10177.3 (2)C11—C12—C17—Cl21.5 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···Oi0.932.553.283 (3)136
C16—H16···Oii0.932.563.416 (3)152
C7—H7···Cl10.932.623.040 (2)108
C11—H11···Cl20.932.633.050 (2)108
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x+1, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC17H12Cl2O
Mr303.17
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)293
a, b, c (Å)14.2816 (4), 8.3056 (2), 25.0612 (7)
V3)2972.69 (14)
Z8
Radiation typeMo Kα
µ (mm1)0.43
Crystal size (mm)0.28 × 0.25 × 0.22
Data collection
DiffractometerBruker SMART APEX CCD area-detector
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
22033, 4611, 2450
Rint0.038
(sin θ/λ)max1)0.719
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.164, 1.00
No. of reflections4611
No. of parameters182
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.47, 0.53

Computer programs: APEX2 (Bruker, 2004), APEX2/SAINT (Bruker, 2004), SAINT/XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 1997), ORTEP-3 for Windows (Farrugia, 1997), 'SHELXL97 (Sheldrick, 1997) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···Oi0.932.553.283 (3)136.0
C16—H16···Oii0.932.563.416 (3)152.4
C7—H7···Cl10.932.623.040 (2)108.4
C11—H11···Cl20.932.633.050 (2)108.4
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x+1, y+1/2, z1/2.
 

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