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In the title compound, [Co(NCS)2(C10H9N3)], a CoII atom with tetra­hedral coordination is bound by two N-donor thio­cyanate anions and two N-donor atoms from two crystallographically distinct di-4-pyridylamine (dpa) ligands whose central NH units lie on twofold axes. The dpa ligands link the Co atoms into one-dimensional [Co(NCS)2(dpa)]n coordination polymer chains that propagate along the b-axis direction.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807049276/pk2052sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536807049276/pk2052Isup2.hkl
Contains datablock I

CCDC reference: 653334

Key indicators

  • Single-crystal X-ray study
  • T = 173 K
  • Mean [sigma](C-C) = 0.005 Å
  • R factor = 0.064
  • wR factor = 0.125
  • Data-to-parameter ratio = 19.4

checkCIF/PLATON results

No syntax errors found



Alert level C RINTA01_ALERT_3_C The value of Rint is greater than 0.10 Rint given 0.116 PLAT020_ALERT_3_C The value of Rint is greater than 0.10 ......... 0.12 PLAT242_ALERT_2_C Check Low Ueq as Compared to Neighbors for C11 PLAT410_ALERT_2_C Short Intra H...H Contact H4 .. H4 .. 1.90 Ang. PLAT420_ALERT_2_C D-H Without Acceptor N4 - H4N ... ? PLAT480_ALERT_4_C Long H...A H-Bond Reported H4N .. S2 .. 2.94 Ang. PLAT480_ALERT_4_C Long H...A H-Bond Reported H4N .. S2 .. 2.94 Ang.
Alert level G PLAT794_ALERT_5_G Check Predicted Bond Valency for Co1 (2) 1.66 PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints ....... 2
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 7 ALERT level C = Check and explain 2 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 3 ALERT type 2 Indicator that the structure model may be wrong or deficient 3 ALERT type 3 Indicator that the structure quality may be low 2 ALERT type 4 Improvement, methodology, query or suggestion 1 ALERT type 5 Informative message, check

Comment top

In comparison to the wide variety of coordination polymers incorporating the rigid rod tethering ligand 4,4'-bipyridine, metal-organic materials based on di-4-pyridylamine (dpa) are much less common (Montney et al., 2007). The title compound was prepared during our continuing attempts to prepare metal pseudohalide/dpa coordination polymers (Knapp et al., 2007). The title compound possesses an asymmetric unit (Fig. 1) consisting of one cobalt atom, two N-bound isothiocyanate anions, and two halves of two crystallographically distinct dpa moieties. Both atoms of each dpa central N–H unit are situated on crystallographic 2-fold rotation axes.

Extension of the structure along the b crystal direction reveals an undulating 1-D chain coordination polymer of formulation [Co(NCS)2(dpa)]n, constructed via the linkage of [CoN4] coordination tetrahedra through the tethering, kinked dpa ligands. The Co–NNCS bond lengths are slightly shorter than the Co–Ndpa bond lengths, likely indicating a modicum of π-donation by the isothiocyanate ligands. The marked undulations in the 1-D chains are imparted by the varied amounts of torsional twisting within the dpa ligands as well as the tetrahedral coordination at cobalt. For one dpa ligand, the inter-ring torsion was measured as 19.6 (3)° via the through-bond/through-space torsion angle C4–C3–C3A–C4A, while the other exhibited a much more pronounced torsional twist of 39.4 (3)° (via the four-atom angle C7–C8–C8A–C7A). Within the 1-D chain motif, the Co–Co distances alternate between 11.464 (1) and 10.985 (1) Å.

As seen in Fig. 2, the 1-D [Co(NCS)2(dpa)]n chains aggregate into discrete pseudo 2-D layers through extensive cooperative ππ stacking interactions between the pyridyl rings of dpa units in neighboring chains (centroid-to-centroid distance = 3.693 (2) Å). Due to this arrangement, the through-space Co–Co distance between neighboring chain motifs within a pseudo 2-D layer is 5.767 (1) Å, over 5 Å closer than the through-ligand Co–Co distance within each chain. The central dpa N–H subunits and pendant sulfur atoms of the isothiocyanate ligands project into the interlamellar regions (Fig. 3), thereby permitting weak bifurcated N–H···S hydrogen bonding interactions between the layers, and propagating the full pseudo 3-D structure of the title compound. The closest Co–Co through-space distances between neighboring pseudo 2-D layers is 11.070 (1) Å.

Related literature top

For related literature, see: Knapp et al. (2007); Montney et al. (2007); Zapf et al. (1998).

Experimental top

Cobalt thiocyanate was obtained commercially. di-4-pyridylamine (dpa) was prepared via a published procedure (Zapf et al., 1998). Cobalt thiocyanate (58 mg, 0.33 mmol) and dpa (114 mg, 0.66 mmol) were added to 10 ml H2O in a 23 ml a Teflon-lined Parr acid digestion bomb. The mixture was then heated under autogenous pressure at 393 K for 48 h., whereupon it was cooled slowly to 293 K. Small dark blue crystals of the title compound were produced, entrained in a pink polycrystalline powder.

Refinement top

All H atoms bound to C atoms were placed in calculated positions, with C—H = 0.93 Å and refined in riding mode with Uiso = 1.2Ueq(C). Both of the H atoms bound to N within the dpa ligands were found via Fourier difference map, restrained with N—H = 0.88 (2) Å, and refined with Uiso =1.2Ueq(N).

Structure description top

In comparison to the wide variety of coordination polymers incorporating the rigid rod tethering ligand 4,4'-bipyridine, metal-organic materials based on di-4-pyridylamine (dpa) are much less common (Montney et al., 2007). The title compound was prepared during our continuing attempts to prepare metal pseudohalide/dpa coordination polymers (Knapp et al., 2007). The title compound possesses an asymmetric unit (Fig. 1) consisting of one cobalt atom, two N-bound isothiocyanate anions, and two halves of two crystallographically distinct dpa moieties. Both atoms of each dpa central N–H unit are situated on crystallographic 2-fold rotation axes.

Extension of the structure along the b crystal direction reveals an undulating 1-D chain coordination polymer of formulation [Co(NCS)2(dpa)]n, constructed via the linkage of [CoN4] coordination tetrahedra through the tethering, kinked dpa ligands. The Co–NNCS bond lengths are slightly shorter than the Co–Ndpa bond lengths, likely indicating a modicum of π-donation by the isothiocyanate ligands. The marked undulations in the 1-D chains are imparted by the varied amounts of torsional twisting within the dpa ligands as well as the tetrahedral coordination at cobalt. For one dpa ligand, the inter-ring torsion was measured as 19.6 (3)° via the through-bond/through-space torsion angle C4–C3–C3A–C4A, while the other exhibited a much more pronounced torsional twist of 39.4 (3)° (via the four-atom angle C7–C8–C8A–C7A). Within the 1-D chain motif, the Co–Co distances alternate between 11.464 (1) and 10.985 (1) Å.

As seen in Fig. 2, the 1-D [Co(NCS)2(dpa)]n chains aggregate into discrete pseudo 2-D layers through extensive cooperative ππ stacking interactions between the pyridyl rings of dpa units in neighboring chains (centroid-to-centroid distance = 3.693 (2) Å). Due to this arrangement, the through-space Co–Co distance between neighboring chain motifs within a pseudo 2-D layer is 5.767 (1) Å, over 5 Å closer than the through-ligand Co–Co distance within each chain. The central dpa N–H subunits and pendant sulfur atoms of the isothiocyanate ligands project into the interlamellar regions (Fig. 3), thereby permitting weak bifurcated N–H···S hydrogen bonding interactions between the layers, and propagating the full pseudo 3-D structure of the title compound. The closest Co–Co through-space distances between neighboring pseudo 2-D layers is 11.070 (1) Å.

For related literature, see: Knapp et al. (2007); Montney et al. (2007); Zapf et al. (1998).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: CrystalMaker (CrystalMaker Software, 2005); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. Asymmetric unit of the title compound, showing 50% probability ellipsoids and partial atom numbering scheme. Color codes: light-blue N, yellow S, black C, pink H, dark blue Co.
[Figure 2] Fig. 2. Aggregation of individual [Co(NCS)2(dpa)]n chains by π-π stacking, shown as dashed lines.
[Figure 3] Fig. 3. Packing diagram illustrating the stacking of the pseudo two-dimensional layers by bifurcated hydrogen bonding patterns (shown as dashed lines) to form the three-dimensional crystal structure of the title compound.
catena-Poly[[bis(thiocyanato-κN)cobalt(II)]-µ- di-4-pyridylamine-κ2N:N'] top
Crystal data top
[Co(NCS)2(C10H9N3)]F(000) = 1400
Mr = 346.31Dx = 1.593 Mg m3
Orthorhombic, PccnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2acCell parameters from 33685 reflections
a = 11.3975 (9) Åθ = 2.3–28.3°
b = 14.8905 (12) ŵ = 1.47 mm1
c = 17.0136 (14) ÅT = 173 K
V = 2887.5 (4) Å3Block, blue
Z = 80.22 × 0.10 × 0.06 mm
Data collection top
Bruker SMART 1K
diffractometer
3576 independent reflections
Radiation source: fine-focus sealed tube2384 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.117
ω scansθmax = 28.3°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1515
Tmin = 0.764, Tmax = 0.915k = 1919
33685 measured reflectionsl = 2222
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)] = 0.064Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0414P)2 + 5.2183P]
where P = (Fo2 + 2Fc2)/3
3576 reflections(Δ/σ)max < 0.001
184 parametersΔρmax = 0.35 e Å3
2 restraintsΔρmin = 0.53 e Å3
Crystal data top
[Co(NCS)2(C10H9N3)]V = 2887.5 (4) Å3
Mr = 346.31Z = 8
Orthorhombic, PccnMo Kα radiation
a = 11.3975 (9) ŵ = 1.47 mm1
b = 14.8905 (12) ÅT = 173 K
c = 17.0136 (14) Å0.22 × 0.10 × 0.06 mm
Data collection top
Bruker SMART 1K
diffractometer
3576 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2384 reflections with I > 2σ(I)
Tmin = 0.764, Tmax = 0.915Rint = 0.117
33685 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0642 restraints
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.35 e Å3
3576 reflectionsΔρmin = 0.53 e Å3
184 parameters
Special details top

Experimental. The small crystal size resulted in relatively weak diffraction and an Rint value in excess of 0.10 despite collection of 30 second frames. Nevertheless, refinement was satisfactory.

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 > 2σ(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
Co10.11826 (4)0.01219 (3)0.27376 (3)0.02166 (15)
S10.38959 (13)0.14244 (13)0.44325 (9)0.0688 (5)
S20.32324 (12)0.12349 (10)0.06501 (8)0.0517 (4)
N10.0002 (3)0.0711 (2)0.32258 (19)0.0224 (7)
N20.25000.25000.4099 (3)0.0350 (13)
H2N0.25000.25000.4619 (12)0.042*
N30.0200 (3)0.1031 (2)0.21497 (18)0.0213 (7)
N40.25000.25000.1100 (3)0.0286 (11)
H4N0.25000.25000.0585 (12)0.034*
N50.2067 (3)0.0673 (2)0.3582 (2)0.0307 (8)
N60.2040 (3)0.0515 (2)0.1925 (2)0.0289 (8)
C10.0077 (4)0.0918 (3)0.3989 (2)0.0333 (10)
H10.04470.06530.43380.040*
C20.0899 (4)0.1506 (3)0.4279 (2)0.0370 (12)
H20.09230.16290.48150.044*
C30.1695 (3)0.1919 (3)0.3779 (2)0.0244 (9)
C40.1645 (4)0.1677 (3)0.3001 (2)0.0291 (10)
H40.21880.19070.26460.035*
C50.0789 (4)0.1094 (3)0.2748 (2)0.0298 (9)
H50.07580.09570.22150.036*
C60.0327 (3)0.1699 (3)0.2534 (2)0.0222 (8)
H60.00780.18270.30420.027*
C70.1216 (3)0.2210 (2)0.2220 (2)0.0250 (8)
H70.15580.26680.25130.030*
C80.1597 (3)0.2033 (2)0.1464 (2)0.0209 (8)
C90.1012 (3)0.1368 (3)0.1044 (2)0.0290 (9)
H90.12150.12500.05250.035*
C100.0133 (4)0.0888 (3)0.1400 (2)0.0276 (9)
H100.02480.04450.11120.033*
C110.2825 (4)0.0991 (3)0.3950 (2)0.0335 (10)
C120.2527 (4)0.0810 (3)0.1386 (2)0.0266 (9)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0196 (3)0.0225 (3)0.0229 (3)0.0014 (2)0.0008 (2)0.0028 (2)
S10.0426 (8)0.1086 (13)0.0550 (9)0.0084 (9)0.0107 (7)0.0464 (9)
S20.0493 (8)0.0760 (10)0.0300 (7)0.0062 (7)0.0046 (6)0.0156 (7)
N10.0203 (16)0.0222 (17)0.0247 (18)0.0004 (13)0.0033 (14)0.0042 (14)
N20.052 (3)0.036 (3)0.017 (2)0.023 (3)0.0000.000
N30.0194 (16)0.0207 (16)0.0239 (18)0.0029 (13)0.0009 (13)0.0017 (14)
N40.030 (3)0.039 (3)0.017 (2)0.015 (2)0.0000.000
N50.0284 (19)0.039 (2)0.0252 (19)0.0045 (16)0.0029 (15)0.0024 (16)
N60.0259 (19)0.0292 (19)0.032 (2)0.0061 (15)0.0004 (16)0.0018 (16)
C10.041 (3)0.036 (3)0.023 (2)0.014 (2)0.0052 (19)0.0010 (19)
C20.049 (3)0.045 (3)0.017 (2)0.021 (2)0.0003 (19)0.0030 (19)
C30.029 (2)0.021 (2)0.024 (2)0.0043 (17)0.0012 (17)0.0015 (17)
C40.026 (2)0.030 (2)0.031 (2)0.0062 (18)0.0109 (18)0.0061 (19)
C50.032 (2)0.038 (2)0.019 (2)0.0061 (18)0.0036 (18)0.0115 (19)
C60.0190 (19)0.029 (2)0.0185 (19)0.0017 (16)0.0017 (15)0.0005 (16)
C70.0249 (19)0.0211 (18)0.029 (2)0.0047 (17)0.0031 (19)0.0037 (17)
C80.0181 (18)0.022 (2)0.022 (2)0.0018 (15)0.0025 (15)0.0017 (16)
C90.031 (2)0.039 (2)0.018 (2)0.0145 (19)0.0007 (17)0.0001 (17)
C100.029 (2)0.029 (2)0.024 (2)0.0078 (18)0.0016 (17)0.0040 (18)
C110.032 (2)0.045 (3)0.024 (2)0.000 (2)0.0040 (19)0.008 (2)
C120.023 (2)0.028 (2)0.030 (2)0.0010 (18)0.0059 (18)0.0064 (18)
Geometric parameters (Å, º) top
Co1—N51.937 (4)N6—C121.157 (5)
Co1—N61.942 (4)C1—C21.375 (6)
Co1—N12.010 (3)C1—H10.9300
Co1—N32.022 (3)C2—C31.388 (5)
S1—C111.606 (5)C2—H20.9300
S2—C121.617 (4)C3—C41.373 (6)
N1—C11.337 (5)C4—C51.375 (5)
N1—C51.342 (5)C4—H40.9300
N2—C3i1.374 (4)C5—H50.9300
N2—C31.374 (4)C6—C71.375 (5)
N2—H2N0.88 (2)C6—H60.9300
N3—C61.333 (5)C7—C81.383 (5)
N3—C101.348 (5)C7—H70.9300
N4—C81.388 (4)C8—C91.391 (5)
N4—C8ii1.388 (4)C9—C101.371 (5)
N4—H4N0.876 (19)C9—H90.9300
N5—C111.167 (5)C10—H100.9300
N5—Co1—N6118.24 (14)C4—C3—N2125.1 (4)
N5—Co1—N1107.65 (14)C4—C3—C2116.7 (4)
N6—Co1—N1109.26 (14)N2—C3—C2118.1 (4)
N5—Co1—N3111.84 (14)C3—C4—C5119.8 (4)
N6—Co1—N3104.70 (14)C3—C4—H4120.1
N1—Co1—N3104.29 (13)C5—C4—H4120.1
C1—N1—C5116.5 (3)N1—C5—C4123.7 (4)
C1—N1—Co1126.1 (3)N1—C5—H5118.1
C5—N1—Co1117.5 (3)C4—C5—H5118.1
C3i—N2—C3133.3 (5)N3—C6—C7123.7 (4)
C3i—N2—H2N113.4 (2)N3—C6—H6118.2
C3—N2—H2N113.4 (2)C7—C6—H6118.2
C6—N3—C10117.1 (3)C6—C7—C8119.1 (3)
C6—N3—Co1120.4 (3)C6—C7—H7120.4
C10—N3—Co1121.2 (3)C8—C7—H7120.4
C8—N4—C8ii127.0 (5)C7—C8—N4123.5 (4)
C8—N4—H4N116.5 (2)C7—C8—C9117.6 (3)
C8ii—N4—H4N116.5 (2)N4—C8—C9118.9 (4)
C11—N5—Co1162.7 (3)C10—C9—C8119.6 (4)
C12—N6—Co1172.1 (3)C10—C9—H9120.2
N1—C1—C2122.8 (4)C8—C9—H9120.2
N1—C1—H1118.6N3—C10—C9122.8 (4)
C2—C1—H1118.6N3—C10—H10118.6
C1—C2—C3120.4 (4)C9—C10—H10118.6
C1—C2—H2119.8N5—C11—S1178.2 (4)
C3—C2—H2119.8N6—C12—S2178.3 (4)
N5—Co1—N1—C16.3 (4)C1—C2—C3—C42.8 (7)
N6—Co1—N1—C1123.3 (4)C1—C2—C3—N2179.9 (4)
N3—Co1—N1—C1125.2 (4)N2—C3—C4—C5179.4 (3)
N5—Co1—N1—C5173.2 (3)C2—C3—C4—C53.8 (6)
N6—Co1—N1—C557.3 (3)C1—N1—C5—C40.6 (6)
N3—Co1—N1—C554.2 (3)Co1—N1—C5—C4179.9 (3)
N5—Co1—N3—C637.7 (3)C3—C4—C5—N12.2 (7)
N6—Co1—N3—C6166.9 (3)C10—N3—C6—C73.3 (5)
N1—Co1—N3—C678.4 (3)Co1—N3—C6—C7164.0 (3)
N5—Co1—N3—C10155.5 (3)N3—C6—C7—C80.2 (6)
N6—Co1—N3—C1026.3 (3)C6—C7—C8—N4178.9 (3)
N1—Co1—N3—C1088.4 (3)C6—C7—C8—C93.0 (6)
N6—Co1—N5—C1121.6 (13)C8ii—N4—C8—C723.5 (3)
N1—Co1—N5—C11145.9 (12)C8ii—N4—C8—C9158.4 (4)
N3—Co1—N5—C11100.1 (12)C7—C8—C9—C103.2 (6)
C5—N1—C1—C21.5 (6)N4—C8—C9—C10178.7 (3)
Co1—N1—C1—C2179.0 (3)C6—N3—C10—C93.1 (6)
N1—C1—C2—C30.2 (7)Co1—N3—C10—C9164.1 (3)
C3i—N2—C3—C411.4 (3)C8—C9—C10—N30.1 (6)
C3i—N2—C3—C2171.7 (4)
Symmetry codes: (i) x1/2, y1/2, z; (ii) x1/2, y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···S1iii0.88 (2)2.78 (1)3.367 (4)126 (1)
N2—H2N···S1iv0.88 (2)2.78 (1)3.367 (4)126 (1)
N4—H4N···S2v0.88 (2)2.94 (2)3.621 (4)136 (1)
N4—H4N···S2vi0.88 (2)2.94 (2)3.621 (4)136 (1)
Symmetry codes: (iii) x, y, z+1; (iv) x1/2, y1/2, z+1; (v) x, y, z; (vi) x1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formula[Co(NCS)2(C10H9N3)]
Mr346.31
Crystal system, space groupOrthorhombic, Pccn
Temperature (K)173
a, b, c (Å)11.3975 (9), 14.8905 (12), 17.0136 (14)
V3)2887.5 (4)
Z8
Radiation typeMo Kα
µ (mm1)1.47
Crystal size (mm)0.22 × 0.10 × 0.06
Data collection
DiffractometerBruker SMART 1K
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.764, 0.915
No. of measured, independent and
observed [I > 2σ(I)] reflections
33685, 3576, 2384
Rint0.117
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.125, 1.06
No. of reflections3576
No. of parameters184
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.35, 0.53

Computer programs: SMART (Bruker, 2001), SAINT-Plus (Bruker, 2003), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), CrystalMaker (CrystalMaker Software, 2005).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···S1i0.88 (2)2.775 (12)3.367 (4)125.6 (3)
N2—H2N···S1ii0.88 (2)2.775 (12)3.367 (4)125.6 (3)
N4—H4N···S2iii0.876 (19)2.943 (15)3.621 (4)135.6 (3)
N4—H4N···S2iv0.876 (19)2.943 (15)3.621 (4)135.6 (3)
Symmetry codes: (i) x, y, z+1; (ii) x1/2, y1/2, z+1; (iii) x, y, z; (iv) x1/2, y+1/2, z.
 

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