Three new Zn^II sulfate complexes

The three zinc sulfate complexes presented herein display three completely different coordination modes, viz tri­aqua(1,10-phenanthroline-N,N′)(sulfato-O)­zinc(II) hydrate, [Zn(SO₄)(C₁₂H₈N₂)(H₂O)₃]·H₂O (octahedral, monomeric), bis(μ-sulfato-O:O′)­bis[(2,9-di­methyl-1,10-phenanthroline-N,N′)­zinc(II)], [Zn₂(SO₄)₂(C₁₄H₁₂N₂)₂] (tetrahedral, dimeric), and catena-poly­[[di­aqua(2,2′-bipyridyl-N,N′)­zinc(II)]-μ-(sul­fato-O:O′)], [Zn(SO₄)(C₁₀H₈N₂)(H₂O)₂]_n (octahedral, polymeric, twofold crystallographic symmetry). In the first, the sulfate is monodentate, while in the other two it acts as a bidentate bridge between two different Zn centers. There is a variety of sulfate S—O bond lengths, depending on the different coordination conditions and hydrogen-bonding interactions.

S1. Comment

The structural study of Zn^II complexes results are particularly attractive since, like most d¹⁰ metal ions, it has the ability to adopt different ways of coordination solely determined by considerations of size as well as electrostatic and covalent bonding forces alone. Besides, when complexed with N– and O-donor ligands its derivatives have an additional interest since such systems are present in some biological molecules of outstanding interest viz: phospholipase C (Huogh et al., 1989); bovine lens leucine aminopeptidase (Burley et al., 1992); etc.

The eventual presence of sulfate as a ligand is expected to introduce additional flexibility into the Zn^II coordination geometry, due to the versatility of the anion in acting either as a monodentate, bidentate or bridging ligand. A search in the Cambridge Structural Database (CSD) confirmed this fact, revealing the existence of 22 reported structures, 14 of which are of a ionic nature and nine constitute real sulfato complexes presenting a variety of coordination modes. In five of them, the anion acts as a simple monodentate ligand, in a diversity of Zn^II environments viz: tetrahedral (Andreetti et al., 1968; Greener et al., 1996), square pyramidal (Zhu Zhi-guo et al., 1990) or octahedral (Hanggi et al., 1988; Dubler et al., 1990); in other two compounds it behaves as a O,O' bridge in linear polymeric chains of ZnO₆ octahedra (Labadi et al., 1993; Shorsheneva et al., 1994). Finally, in the remaining two it presents a much more complex coordination viz: in µ₄-sulfido)-hexakis (µ₃-sulfido)-tris(µ₃-sulfato)-nonakis(pyridyl)-deca-zinc trihydrate (Ali et al., 1998) it binds to three different Zn centers as a triply monodentate ligand, fulfilling the role of a multiple link in an extremely intricate three-dimensional network, while in catena-[(µ₂-4,4'-bipyridyl)-aqua-(µ₂-sulfato-O,O',O'')]zinc hemihydrate) (Songping et al., 1998) it links to two different Zn centers, monocordinated to one and bicordinated to the other, also giving rise to a complex structure. Recently, the structure of tetraaqua(1,10-phenanthroline) zinc(II) sulfate hydrate has been reported, in which the anion is not coordinated to the metal (Zhang et al., 1999)

As a part of a general structural work on sulfur oxyanions, we report herein the synthesis and structural determination of three novel Zn^II sulfate complexes: triaqua(1,10-phenanthroline-N,N')(sulfato-O)zinc(II) hydrate, (I); di-µ-(sulfato-O:O')bis(2,9-dimethyl-1,10-phenanthroline)zinc(II), (II), whose coordination is unprecedented in the literature, and catena-poly[diaqua(2,2'-bipyridyl-N,N') zinc(II)-µ-(sulfato-O:O')], (III). \sch

The structure of (I) is made up of monomers (Fig. 1) strongly inter-linked by hydrogen bonding. The environment of the cation is octahedral, the bidentate bipy and two aqua molecules occupying the equatorial sites, with a third aqua and one of the sulfate O atoms (the only one involved in direct coordination to the cation) filling the apical sites. There is a strong intramolecular hydrogen bond, between one of the coordinated water molecules (O2W) and a second oxygen from the sulfate anion (O4). The rest of the available H atoms take part in important hydrogen-bonding interactions (Table 1) which give rise to a rather complex three-dimensional structure. The oxygen O4, in particular, is acceptor of three of them, a fact which seems to weaken the S—O4 bond (see below).

In the neocuproine sulfate, (II), the sulfate acts as a O—S—O bridge across two different Zn^II nuclei, determining the formation of a dimer (Fig. 2). The cation environment is tetrahedral, the coordination being completed by a bidentate neocuproine. The structure is doubly unique in that it is the first sulfato-bridged zinc(II) dimer reported, and it is the first Zn^II complex with a tetrahedral ZnN₂O₂ environment which includes a bidentate N—Zn—N bite. No hydrogen bonding is present in the structure due to the absence of H donors.

Finally, the bipyridine structure is a polymer made up of ZnN₂O₄ octahedra, with a twofold axis bisecting the coordination polyhedron through the cation and the central point of the bipy ligand. As a result, only half of the group is independent (Fig. 3). The equatorial plane is similarly defined as the one in (I), but the apical sites are provided by a single oxygen from the sulfate group. The latter anion, in turn, is also bisected by a second twofold axis thus rendering only two O atoms independent: the one involved in coordination to Zn and a second one which takes part in two important hydrogen bonds: an intramolecular one, with one of the two aqua H atoms, H1WA, and an intermolecular one with the remaining hydrogen H1WB.

A systematic analysis of the three structures leads to the conclusion that the S—O bond lengths are quite sensible to the degree of compromise with which the O atoms are involved in any extra interaction, be it coordination or hydrogen bonding. Thus, when coordination is achieved through a mild interaction viz, through the occupation of an apical site in a Jahn Teller distorted octahedra [cases (I) and (III)], the S—O distance hardly departs from average. Instead, when the coordination interaction is strong [case (II)] or the hydrogen bonds in which it takes part are strong and multiple [case of the triple acceptor O4 in (I)] the S—O weakens sensibly, with appreciable lengthening of up to 4–5%.

S2. Experimental

The three compounds were obtained by diffusion, with a similar setup: this consisted of two vessels, the first one containing an aqueous solution of Zn sulfate [0.050 M in (I) and (II), and 0.025 M in (III)] and the second, a methanolic solution of the corresponding organic ligand. The link between both solutions was achieved though a connecting pipe full of water, and after a rather long time (one to two months) some crystals adequate for X-ray diffraction appeared, usually in the connecting media and far from the original solutions. It was not uncommon to have crystals growing in different sections of the setup, which proved to be the same compounds though displaying quite different habits. The characteristics reported herein are those of the crystals actually measured.

S3. Refinement

The structures were conventionally solved by direct methods and refined by least squares on F². Anisotropic displacement factors were applied to non-H atoms. H atoms attached to carbon were idealized and allowed to ride, except those pertaining to the methyl groups, which were also allowed to rotate around the C—C bond. Those attached to oxygen were found in the difference Fourier map and refined with individual isotropic displacement factors.

Computing details

For all compounds, data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1988); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: MSC/AFC Diffractometer Control Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL/PC (Sheldrick, 1994); software used to prepare material for publication: PARST (Nardelli, 1983) and CSD (Allen Kennard, 1993).

Figures

	Fig. 1. Molecular diagram for (I). Displacement ellipsoids are drawn at a 50% level. Light broken lines depict intermolecular hydrogen-bonding interactions; heavy broken lines, intramolecular ones [symmetry codes: (') 2 − x, 1 − y, 1 − z; (") 1 − x, 1 − y, −z; (*) x, y, 1 + z].
	Fig. 2. Molecular diagram for (II) showing the dimer formed around the symmetry center. Displacement ellipsoids are drawn at a 50% level.
	Fig. 3. Molecular diagram for (III). Note the twofold axis across the coordination polyhedron through the cation. Displacement ellipsoids are drawn at a 50% level. Light broken lines depict intermolecular hydrogen-bonding interactions; heavy broken lines, intramolecular ones. [Symmetry codes: (') −x, y, 1/2 − z; (") x, 1 − y, 1/2 + z; (*) x, y, 1 + z].

(I) Tri-aqua(zinc(II) 1,10-phenanthroline sulfate), hydrate

Crystal data

[Zn(SO4)(C12H8N2)(H2O)3]·H2O	Z = 2
Mr = 413.70	F(000) = 424
Triclinic, P1	Dx = 1.757 Mg m^−3
a = 8.641 (3) Å	Mo Kα radiation, λ = 0.71073 Å
b = 11.600 (3) Å	Cell parameters from 25 reflections
c = 8.046 (1) Å	θ = 7.5–15°
α = 92.11°	µ = 1.75 mm^−1
β = 103.77 (3)°	T = 293 K
γ = 92.06°	Prismatic, colorless
V = 782.0 (4) Å^3	0.35 × 0.25 × 0.18 mm

Data collection

Rigaku AFC7S Difractometer diffractometer	3355 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.026
Graphite monochromator	θmax = 27.5°, θmin = 2.4°
ω/2θ scans	h = −8→11
Absorption correction: ψ scan (MSC/AFC Diffractometer Control Software; Molecular Structure Corporation, 1988)	k = −15→15
Tmin = 0.63, Tmax = 0.73	l = −10→10
4231 measured reflections	3 standard reflections every 150 reflections
3591 independent reflections	intensity decay: <3%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: geom+difmap
R[F^2 > 2σ(F^2)] = 0.032	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.090	Calculated w = 1/[σ^2(Fo^2) + (0.037P)^2 + 0.496P] where P = (Fo^2 + 2Fc^2)/3
S = 1.03	(Δ/σ)max < 0.01
3591 reflections	Δρmax = 0.69 e Å^−3
251 parameters	Δρmin = −0.58 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.106 (4)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zn	0.75855 (3)	0.696082 (17)	0.19472 (3)	0.02241 (12)
S	0.55260 (6)	0.65281 (4)	−0.22243 (6)	0.02304 (14)
O1	0.6041 (2)	0.71481 (15)	−0.3561 (2)	0.0407 (4)
O2	0.37763 (19)	0.63521 (14)	−0.2675 (2)	0.0332 (3)
O3	0.6043 (2)	0.71755 (13)	−0.05536 (19)	0.0317 (3)
O4	0.6233 (2)	0.53596 (13)	−0.2069 (2)	0.0310 (3)
N1	0.7612 (2)	0.87486 (15)	0.2673 (2)	0.0238 (3)
N2	0.9720 (2)	0.76087 (14)	0.1332 (2)	0.0241 (3)
C1	0.6520 (3)	0.9311 (2)	0.3271 (3)	0.0332 (5)
H1C	0.5583	0.8886	0.3394	0.080*
C2	0.6696 (3)	1.0497 (2)	0.3727 (3)	0.0402 (6)
H2C	0.5869	1.0879	0.4113	0.080*
C3	0.8053 (3)	1.11001 (19)	0.3617 (3)	0.0383 (6)
H3C	0.8198	1.1907	0.3953	0.080*
C4	0.9235 (3)	1.05338 (17)	0.3004 (3)	0.0297 (5)
C5	1.0680 (3)	1.10968 (19)	0.2809 (3)	0.0361 (5)
H5A	1.0901	1.1896	0.3172	0.080*
C6	1.1734 (3)	1.0531 (2)	0.2131 (3)	0.0362 (5)
H6A	1.2683	1.0935	0.1998	0.080*
C7	1.1460 (3)	0.93304 (19)	0.1606 (3)	0.0284 (4)
C8	1.2506 (3)	0.8698 (2)	0.0862 (3)	0.0345 (5)
H8A	1.3463	0.9069	0.0688	0.080*
C9	1.2154 (3)	0.7557 (2)	0.0387 (3)	0.0368 (5)
H9A	1.2864	0.7118	−0.0110	0.080*
C10	1.0742 (3)	0.70396 (19)	0.0640 (3)	0.0328 (5)
H10A	1.0503	0.6238	0.0303	0.080*
C11	1.0071 (2)	0.87362 (16)	0.1809 (2)	0.0226 (4)
C12	0.8932 (3)	0.93490 (16)	0.2522 (2)	0.0232 (4)
O1W	0.9181 (2)	0.65373 (15)	0.4379 (2)	0.0309 (3)
H1WA	1.003 (4)	0.625 (3)	0.420 (4)	0.045 (8)*
H1WB	0.879 (4)	0.610 (3)	0.485 (4)	0.034 (8)*
O2W	0.7791 (2)	0.52569 (13)	0.1176 (2)	0.0306 (3)
H2WA	0.721 (5)	0.523 (4)	0.025 (6)	0.069 (12)*
H2WB	0.735 (4)	0.480 (3)	0.170 (4)	0.040 (8)*
O3W	0.5696 (2)	0.66139 (14)	0.3062 (2)	0.0301 (3)
H3WA	0.508 (4)	0.604 (3)	0.273 (4)	0.039 (8)*
H3WB	0.586 (4)	0.670 (3)	0.417 (5)	0.053 (9)*
O4W	0.8039 (2)	0.45698 (18)	0.5733 (3)	0.0387 (4)
H4WA	0.736 (5)	0.431 (4)	0.500 (6)	0.070 (13)*
H4WB	0.757 (4)	0.479 (3)	0.641 (5)	0.054 (10)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn	0.02813 (16)	0.01688 (15)	0.02337 (15)	−0.00429 (9)	0.01003 (10)	−0.00420 (9)
S	0.0308 (3)	0.0210 (2)	0.0177 (2)	−0.00746 (18)	0.00866 (18)	−0.00529 (17)
O1	0.0604 (11)	0.0379 (9)	0.0264 (8)	−0.0204 (8)	0.0197 (8)	−0.0030 (7)
O2	0.0311 (8)	0.0337 (8)	0.0341 (8)	−0.0054 (6)	0.0080 (6)	−0.0026 (6)
O3	0.0469 (9)	0.0250 (7)	0.0208 (7)	0.0004 (7)	0.0050 (6)	−0.0082 (6)
O4	0.0385 (8)	0.0252 (7)	0.0297 (8)	−0.0012 (6)	0.0109 (6)	−0.0105 (6)
N1	0.0286 (8)	0.0211 (8)	0.0218 (8)	−0.0004 (6)	0.0070 (6)	−0.0032 (6)
N2	0.0298 (9)	0.0183 (7)	0.0257 (8)	−0.0018 (6)	0.0105 (7)	−0.0019 (6)
C1	0.0371 (12)	0.0331 (11)	0.0309 (11)	0.0049 (9)	0.0115 (9)	−0.0032 (9)
C2	0.0529 (15)	0.0333 (12)	0.0376 (12)	0.0140 (11)	0.0166 (11)	−0.0051 (10)
C3	0.0621 (16)	0.0214 (10)	0.0308 (11)	0.0064 (10)	0.0100 (11)	−0.0054 (8)
C4	0.0447 (12)	0.0181 (9)	0.0225 (9)	−0.0020 (8)	0.0015 (8)	−0.0026 (7)
C5	0.0533 (14)	0.0182 (9)	0.0309 (11)	−0.0115 (9)	0.0010 (10)	−0.0030 (8)
C6	0.0407 (13)	0.0290 (11)	0.0337 (11)	−0.0155 (9)	0.0009 (9)	0.0020 (9)
C7	0.0301 (10)	0.0278 (10)	0.0245 (9)	−0.0076 (8)	0.0023 (8)	0.0019 (8)
C8	0.0266 (10)	0.0420 (12)	0.0346 (11)	−0.0074 (9)	0.0078 (9)	0.0050 (9)
C9	0.0367 (12)	0.0396 (12)	0.0398 (12)	0.0050 (10)	0.0198 (10)	0.0019 (10)
C10	0.0382 (12)	0.0265 (10)	0.0379 (12)	0.0021 (9)	0.0180 (10)	−0.0022 (8)
C11	0.0279 (10)	0.0190 (9)	0.0193 (8)	−0.0030 (7)	0.0032 (7)	−0.0004 (7)
C12	0.0324 (10)	0.0180 (8)	0.0173 (8)	−0.0015 (7)	0.0029 (7)	−0.0016 (6)
O1W	0.0329 (8)	0.0299 (8)	0.0311 (8)	−0.0001 (7)	0.0103 (7)	0.0006 (6)
O2W	0.0427 (9)	0.0203 (7)	0.0287 (8)	−0.0035 (6)	0.0099 (7)	−0.0034 (6)
O3W	0.0340 (8)	0.0313 (8)	0.0262 (8)	−0.0106 (7)	0.0123 (6)	−0.0057 (6)
O4W	0.0313 (9)	0.0535 (11)	0.0320 (9)	0.0021 (8)	0.0102 (8)	−0.0047 (8)

Geometric parameters (Å, º)

Zn—O2W	2.076 (2)	C4—C5	1.432 (4)
Zn—O3W	2.076 (2)	C5—C6	1.346 (4)
Zn—N1	2.132 (2)	C5—H5A	0.9600
Zn—N2	2.138 (2)	C6—C7	1.435 (3)
Zn—O3	2.161 (2)	C6—H6A	0.9600
Zn—O1W	2.192 (2)	C7—C11	1.409 (3)
S—O1	1.461 (2)	C7—C8	1.409 (3)
S—O2	1.473 (2)	C8—C9	1.367 (4)
S—O3	1.479 (2)	C8—H8A	0.9600
S—O4	1.504 (2)	C9—C10	1.401 (3)
N1—C1	1.335 (3)	C9—H9A	0.9601
N1—C12	1.347 (3)	C10—H10A	0.9600
N2—C10	1.333 (3)	C11—C12	1.446 (3)
N2—C11	1.352 (2)	O1W—H1WA	0.85 (4)
C1—C2	1.404 (3)	O1W—H1WB	0.76 (3)
C1—H1C	0.9600	O2W—H2WA	0.79 (5)
C2—C3	1.367 (4)	O2W—H2WB	0.83 (3)
C2—H2C	0.9600	O3W—H3WA	0.83 (3)
C3—C4	1.408 (3)	O3W—H3WB	0.87 (4)
C3—H3C	0.9600	O4W—H4WA	0.77 (5)
C4—C12	1.412 (3)	O4W—H4WB	0.80 (4)
O2W—Zn—O3W	95.17 (7)	C3—C4—C12	116.9 (2)
O2W—Zn—N1	173.89 (7)	C3—C4—C5	123.8 (2)
O3W—Zn—N1	90.82 (7)	C12—C4—C5	119.3 (2)
O2W—Zn—N2	95.82 (7)	C6—C5—C4	121.5 (2)
O3W—Zn—N2	165.87 (7)	C6—C5—H5A	119.3
N1—Zn—N2	78.07 (7)	C4—C5—H5A	119.2
O2W—Zn—O3	87.81 (6)	C5—C6—C7	120.9 (2)
O3W—Zn—O3	93.44 (7)	C5—C6—H6A	119.6
N1—Zn—O3	93.06 (6)	C7—C6—H6A	119.5
N2—Zn—O3	95.84 (7)	C11—C7—C8	117.1 (2)
O2W—Zn—O1W	85.53 (7)	C11—C7—C6	119.5 (2)
O3W—Zn—O1W	87.42 (7)	C8—C7—C6	123.4 (2)
N1—Zn—O1W	93.53 (6)	C9—C8—C7	119.8 (2)
N2—Zn—O1W	84.60 (7)	C9—C8—H8A	120.1
O3—Zn—O1W	173.34 (6)	C7—C8—H8A	120.0
O1—S—O2	109.95 (11)	C8—C9—C10	119.0 (2)
O1—S—O3	110.73 (10)	C8—C9—H9A	120.4
O2—S—O3	109.58 (10)	C10—C9—H9A	120.6
O1—S—O4	109.80 (10)	N2—C10—C9	123.0 (2)
O2—S—O4	107.90 (9)	N2—C10—H10A	118.5
O3—S—O4	108.82 (9)	C9—C10—H10A	118.5
S—O3—Zn	138.61 (10)	N2—C11—C7	123.05 (19)
C1—N1—C12	118.20 (18)	N2—C11—C12	117.42 (18)
C1—N1—Zn	128.17 (16)	C7—C11—C12	119.51 (18)
C12—N1—Zn	113.61 (13)	N1—C12—C4	123.3 (2)
C10—N2—C11	118.05 (18)	N1—C12—C11	117.40 (17)
C10—N2—Zn	128.68 (15)	C4—C12—C11	119.30 (19)
C11—N2—Zn	113.18 (13)	Zn—O1W—H1WA	110 (2)
N1—C1—C2	122.4 (2)	Zn—O1W—H1WB	112 (2)
N1—C1—H1C	118.6	H1WA—O1W—H1WB	108 (3)
C2—C1—H1C	118.9	Zn—O2W—H2WA	101 (3)
C3—C2—C1	119.4 (2)	Zn—O2W—H2WB	112 (2)
C3—C2—H2C	120.4	H2WA—O2W—H2WB	103 (3)
C1—C2—H2C	120.2	Zn—O3W—H3WA	121 (2)
C2—C3—C4	119.7 (2)	Zn—O3W—H3WB	119 (2)
C2—C3—H3C	120.1	H3WA—O3W—H3WB	108 (3)
C4—C3—H3C	120.2	H4WA—O4W—H4WB	102 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O4W^i	0.86 (4)	1.94 (3)	2.783 (3)	167 (3)
O1W—H1WB···O4W	0.76 (3)	2.07 (3)	2.812 (3)	163 (3)
O2W—H2WA···O4	0.80 (4)	1.86 (4)	2.647 (2)	166 (4)
O2W—H2WB···O2^ii	0.83 (4)	1.92 (3)	2.746 (3)	174 (3)
O3W—H3WA···O4^ii	0.83 (3)	1.93 (3)	2.760 (2)	175 (3)
O3W—H3WB···O1^iii	0.87 (4)	1.85 (4)	2.708 (2)	169 (3)
O4W—H4WA···O2^ii	0.78 (4)	2.00 (4)	2.740 (2)	159 (4)
O4W—H4WB···O4^iii	0.80 (4)	1.98 (4)	2.775 (3)	175 (4)

Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x+1, −y+1, −z; (iii) x, y, z+1.

(II) Bis(zinc(II) 2,9-dimethyl-1,10-phenanthroline sulfate)

Crystal data

[Zn2(SO4)2(C14H12N2)2]	Z = 1
Mr = 739.37	F(000) = 376
Triclinic, P1	Dx = 1.785 Mg m^−3
a = 8.8044 (15) Å	Mo Kα radiation, λ = 0.71070 Å
b = 10.4281 (13) Å	Cell parameters from 25 reflections
c = 8.7719 (12) Å	θ = 7.5–15°
α = 103.738 (12)°	µ = 1.96 mm^−1
β = 99.385 (14)°	T = 293 K
γ = 113.357 (11)°	Prismatic, colorless
V = 687.70 (17) Å^3	0.40 × 0.28 × 0.20 mm

Data collection

Rigaku AFC7S Difractometer diffractometer	2966 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.031
Graphite monochromator	θmax = 27.5°, θmin = 2.3°
ω/2θ scans	h = −2→11
Absorption correction: ψ scan (MSC/AFC Diffractometer Control Software; Molecular Structure Corporation, 1988)	k = −13→13
Tmin = 0.56, Tmax = 0.68	l = −11→11
4198 measured reflections	3 standard reflections every 150 reflections
3175 independent reflections	intensity decay: <3%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: geom+difmap
R[F^2 > 2σ(F^2)] = 0.033	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.096	Calculated w = 1/[σ^2(Fo^2) + (0.054P)^2 + 0.43P] where P = (Fo^2 + 2Fc^2)/3
S = 1.08	(Δ/σ)max < 0.01
3175 reflections	Δρmax = 0.85 e Å^−3
202 parameters	Δρmin = −0.62 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.055 (4)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zn	0.21595 (3)	0.17175 (3)	0.07365 (3)	0.02792 (12)
S	−0.09980 (7)	0.10451 (6)	0.20524 (7)	0.02828 (15)
O1	0.0565 (2)	0.0814 (2)	0.1877 (2)	0.0390 (4)
O2	−0.2518 (2)	−0.0303 (2)	0.0824 (2)	0.0418 (4)
O3	−0.1149 (3)	0.1113 (3)	0.3676 (2)	0.0502 (5)
O4	−0.0845 (3)	0.2345 (2)	0.1662 (3)	0.0540 (5)
N1	0.4504 (2)	0.3058 (2)	0.2464 (2)	0.0276 (4)
N2	0.2461 (2)	0.3651 (2)	0.0375 (2)	0.0282 (4)
C1	0.5513 (3)	0.2696 (3)	0.3390 (3)	0.0332 (5)
C2	0.7075 (3)	0.3808 (3)	0.4549 (3)	0.0432 (6)
H2B	0.7814	0.3537	0.5190	0.080*
C3	0.7539 (3)	0.5269 (3)	0.4768 (3)	0.0437 (6)
H3B	0.8586	0.6023	0.5582	0.080*
C4	0.6484 (3)	0.5670 (3)	0.3797 (3)	0.0348 (5)
C5	0.6882 (4)	0.7164 (3)	0.3902 (3)	0.0419 (6)
H5A	0.7891	0.7964	0.4723	0.080*
C6	0.5860 (4)	0.7461 (3)	0.2865 (3)	0.0424 (6)
H6A	0.6153	0.8472	0.2957	0.080*
C7	0.4342 (3)	0.6297 (3)	0.1627 (3)	0.0350 (5)
C8	0.3258 (4)	0.6532 (3)	0.0467 (4)	0.0415 (6)
H8A	0.3514	0.7521	0.0488	0.080*
C9	0.1849 (4)	0.5351 (3)	−0.0681 (3)	0.0408 (6)
H9A	0.1119	0.5513	−0.1474	0.080*
C10	0.1455 (3)	0.3890 (3)	−0.0714 (3)	0.0331 (5)
C11	0.4976 (3)	0.4508 (2)	0.2631 (3)	0.0283 (4)
C12	0.3884 (3)	0.4818 (2)	0.1521 (3)	0.0288 (4)
C13	0.4930 (4)	0.1087 (3)	0.3146 (4)	0.0436 (6)
H13A	0.3897	0.0702	0.3474	0.052*
H13B	0.5820	0.0967	0.3798	0.052*
H13C	0.4700	0.0559	0.2011	0.052*
C14	−0.0077 (4)	0.2583 (3)	−0.1956 (3)	0.0414 (6)
H14A	0.0258	0.1841	−0.2421	0.050*
H14B	−0.0524	0.2882	−0.2807	0.050*
H14C	−0.0953	0.2183	−0.1440	0.050*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn	0.02259 (16)	0.02048 (16)	0.03504 (17)	0.00519 (11)	0.00683 (11)	0.00878 (11)
S	0.0235 (3)	0.0219 (3)	0.0340 (3)	0.0061 (2)	0.0075 (2)	0.0080 (2)
O1	0.0296 (8)	0.0421 (10)	0.0547 (10)	0.0168 (8)	0.0190 (8)	0.0267 (8)
O2	0.0258 (8)	0.0331 (9)	0.0465 (10)	0.0045 (7)	0.0087 (7)	−0.0038 (7)
O3	0.0382 (10)	0.0652 (14)	0.0361 (9)	0.0147 (10)	0.0122 (8)	0.0128 (9)
O4	0.0555 (12)	0.0358 (10)	0.0812 (15)	0.0241 (10)	0.0216 (11)	0.0300 (10)
N1	0.0219 (8)	0.0229 (8)	0.0328 (9)	0.0064 (7)	0.0068 (7)	0.0078 (7)
N2	0.0279 (9)	0.0238 (9)	0.0346 (9)	0.0105 (7)	0.0122 (7)	0.0130 (7)
C1	0.0260 (10)	0.0333 (12)	0.0380 (11)	0.0122 (9)	0.0083 (9)	0.0111 (9)
C2	0.0306 (12)	0.0452 (15)	0.0423 (13)	0.0127 (11)	−0.0002 (10)	0.0105 (11)
C3	0.0296 (12)	0.0383 (13)	0.0410 (13)	0.0035 (10)	0.0033 (10)	0.0014 (10)
C4	0.0279 (11)	0.0269 (11)	0.0365 (11)	0.0025 (9)	0.0120 (9)	0.0041 (9)
C5	0.0370 (13)	0.0235 (11)	0.0455 (13)	−0.0010 (9)	0.0157 (11)	0.0012 (9)
C6	0.0480 (15)	0.0205 (10)	0.0532 (14)	0.0063 (10)	0.0274 (12)	0.0103 (10)
C7	0.0424 (13)	0.0248 (11)	0.0430 (12)	0.0134 (10)	0.0251 (10)	0.0148 (9)
C8	0.0575 (16)	0.0314 (12)	0.0535 (14)	0.0252 (12)	0.0328 (13)	0.0244 (11)
C9	0.0515 (15)	0.0436 (15)	0.0482 (14)	0.0308 (13)	0.0251 (12)	0.0274 (12)
C10	0.0348 (12)	0.0361 (12)	0.0385 (11)	0.0200 (10)	0.0170 (9)	0.0183 (10)
C11	0.0242 (10)	0.0225 (10)	0.0324 (10)	0.0054 (8)	0.0118 (8)	0.0063 (8)
C12	0.0297 (10)	0.0207 (10)	0.0355 (10)	0.0084 (8)	0.0166 (9)	0.0092 (8)
C13	0.0415 (14)	0.0366 (13)	0.0527 (15)	0.0200 (11)	0.0061 (11)	0.0157 (11)
C14	0.0375 (13)	0.0462 (15)	0.0430 (13)	0.0212 (12)	0.0072 (10)	0.0183 (11)

Geometric parameters (Å, º)

Zn—O2^i	1.923 (2)	C4—C5	1.431 (4)
Zn—O1	1.928 (2)	C5—C6	1.350 (4)
Zn—N2	2.035 (2)	C5—H5A	0.9600
Zn—N1	2.049 (2)	C6—C7	1.433 (4)
S—O4	1.437 (2)	C6—H6A	0.9600
S—O3	1.439 (2)	C7—C12	1.406 (3)
S—O2	1.499 (2)	C7—C8	1.411 (4)
S—O1	1.513 (2)	C8—C9	1.364 (4)
N1—C1	1.329 (3)	C8—H8A	0.9600
N1—C11	1.363 (3)	C9—C10	1.413 (3)
N2—C10	1.332 (3)	C9—H9A	0.9599
N2—C12	1.364 (3)	C10—C14	1.491 (4)
C1—C2	1.410 (3)	C11—C12	1.438 (3)
C1—C13	1.495 (4)	C13—H13A	0.9600
C2—C3	1.367 (4)	C13—H13B	0.9600
C2—H2B	0.9599	C13—H13C	0.9600
C3—C4	1.408 (4)	C14—H14A	0.9600
C3—H3B	0.9600	C14—H14B	0.9600
C4—C11	1.404 (3)	C14—H14C	0.9600
O2^i—Zn—O1	112.96 (8)	C4—C5—H5A	119.4
O2^i—Zn—N2	119.61 (8)	C5—C6—C7	121.4 (2)
O1—Zn—N2	121.21 (8)	C5—C6—H6A	119.5
O2^i—Zn—N1	105.96 (8)	C7—C6—H6A	119.2
O1—Zn—N1	106.67 (8)	C12—C7—C8	116.7 (2)
N2—Zn—N1	83.00 (8)	C12—C7—C6	119.3 (2)
O4—S—O3	113.77 (15)	C8—C7—C6	124.1 (2)
O4—S—O2	110.12 (13)	C9—C8—C7	119.9 (2)
O3—S—O2	109.26 (12)	C9—C8—H8A	120.2
O4—S—O1	108.93 (12)	C7—C8—H8A	119.9
O3—S—O1	109.01 (12)	C8—C9—C10	120.6 (2)
O2—S—O1	105.41 (11)	C8—C9—H9A	119.7
S—O1—Zn	126.04 (11)	C10—C9—H9A	119.7
S—O2—Zn^i	120.00 (11)	N2—C10—C9	120.2 (2)
C1—N1—C11	120.07 (19)	N2—C10—C14	118.2 (2)
C1—N1—Zn	129.36 (16)	C9—C10—C14	121.6 (2)
C11—N1—Zn	110.55 (15)	N1—C11—C4	122.5 (2)
C10—N2—C12	119.9 (2)	N1—C11—C12	117.27 (19)
C10—N2—Zn	129.53 (16)	C4—C11—C12	120.2 (2)
C12—N2—Zn	110.46 (14)	N2—C12—C7	122.7 (2)
N1—C1—C2	120.3 (2)	N2—C12—C11	118.13 (19)
N1—C1—C13	117.6 (2)	C7—C12—C11	119.2 (2)
C2—C1—C13	122.1 (2)	C1—C13—H13A	109.5
C3—C2—C1	120.3 (2)	C1—C13—H13B	109.5
C3—C2—H2B	119.8	H13A—C13—H13B	109.5
C1—C2—H2B	119.8	C1—C13—H13C	109.5
C2—C3—C4	120.0 (2)	H13A—C13—H13C	109.5
C2—C3—H3B	120.0	H13B—C13—H13C	109.5
C4—C3—H3B	120.0	C10—C14—H14A	109.5
C11—C4—C3	116.7 (2)	C10—C14—H14B	109.5
C11—C4—C5	119.1 (2)	H14A—C14—H14B	109.5
C3—C4—C5	124.2 (2)	C10—C14—H14C	109.5
C6—C5—C4	120.9 (2)	H14A—C14—H14C	109.5
C6—C5—H5A	119.7	H14B—C14—H14C	109.5

Symmetry code: (i) −x, −y, −z.

(III) Di-aqua(zinc(II) bipyridil sulfate)

Crystal data

[Zn(SO4)(C10H8N2)(H2O)2]	F(000) = 720
Mr = 353.65	Dx = 1.833 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 15.421 (3) Å	Cell parameters from 25 reflections
b = 12.701 (3) Å	θ = 7.5–15°
c = 6.694 (1) Å	µ = 2.11 mm^−1
β = 102.13 (3)°	T = 293 K
V = 1281.8 (4) Å^3	Plate, colorless
Z = 4	0.25 × 0.22 × 0.12 mm

Data collection

Rigaku AFC7S Difractometer diffractometer	1099 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.026
Graphite monochromator	θmax = 27.5°, θmin = 2.1°
ω/2θ scans	h = 0→20
Absorption correction: ψ scan (MSC/AFC Diffractometer Control Software; Molecular Structure Corporation, 1988)	k = 0→16
Tmin = 0.60, Tmax = 0.78	l = −8→8
1524 measured reflections	3 standard reflections every 150 reflections
1473 independent reflections	intensity decay: <3%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: geom+difmap
R[F^2 > 2σ(F^2)] = 0.029	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.085	Calculated w = 1/[σ^2(Fo^2)] where P = (Fo^2 + 2Fc^2)/3
S = 1.02	(Δ/σ)max < 0.01
1473 reflections	Δρmax = 0.37 e Å^−3
102 parameters	Δρmin = −0.39 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0045 (4)

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Zn	0.0000	0.27590 (3)	0.2500	0.02180 (16)
S	0.0000	0.34307 (7)	−0.2500	0.0221 (2)
O1	−0.02369 (16)	0.27637 (15)	−0.0897 (3)	0.0337 (5)
O2	−0.07592 (14)	0.41057 (15)	−0.3428 (3)	0.0319 (5)
N1	−0.08714 (15)	0.14648 (17)	0.2239 (3)	0.0212 (5)
C1	−0.17580 (19)	0.1532 (2)	0.1948 (4)	0.0281 (6)
H1	−0.2019	0.2195	0.1851	0.034*
C2	−0.2297 (2)	0.0655 (3)	0.1788 (5)	0.0347 (7)
H2	−0.2909	0.0724	0.1603	0.042*
C3	−0.1905 (2)	−0.0324 (2)	0.1908 (5)	0.0349 (7)
H3	−0.2252	−0.0929	0.1803	0.042*
C4	−0.0994 (2)	−0.0401 (2)	0.2187 (4)	0.0287 (6)
H4	−0.0720	−0.1057	0.2263	0.034*
C5	−0.04939 (17)	0.05134 (19)	0.2350 (4)	0.0206 (5)
O1W	−0.09831 (15)	0.38539 (15)	0.2556 (3)	0.0266 (4)
H1WA	−0.090 (3)	0.391 (3)	0.371 (4)	0.043 (11)*
H1WB	−0.090 (2)	0.438 (2)	0.211 (4)	0.037 (11)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn	0.0244 (3)	0.0146 (2)	0.0275 (3)	0.000	0.00815 (18)	0.000
S	0.0353 (5)	0.0153 (4)	0.0181 (4)	0.000	0.0108 (4)	0.000
O1	0.0560 (14)	0.0290 (11)	0.0175 (10)	−0.0181 (10)	0.0111 (9)	−0.0009 (8)
O2	0.0380 (12)	0.0280 (11)	0.0309 (11)	0.0094 (9)	0.0101 (10)	−0.0037 (9)
N1	0.0252 (12)	0.0188 (10)	0.0204 (11)	−0.0021 (9)	0.0062 (9)	0.0011 (8)
C1	0.0260 (14)	0.0295 (15)	0.0291 (15)	0.0031 (12)	0.0064 (12)	0.0030 (12)
C2	0.0234 (14)	0.0470 (17)	0.0339 (17)	−0.0067 (14)	0.0062 (13)	0.0016 (14)
C3	0.0377 (16)	0.0347 (15)	0.0324 (15)	−0.0166 (14)	0.0075 (13)	−0.0003 (13)
C4	0.0385 (16)	0.0214 (13)	0.0261 (14)	−0.0046 (12)	0.0067 (12)	0.0015 (11)
C5	0.0265 (14)	0.0195 (12)	0.0161 (11)	−0.0022 (10)	0.0049 (10)	−0.0001 (10)
O1W	0.0338 (12)	0.0193 (10)	0.0272 (11)	0.0042 (9)	0.0080 (9)	0.0032 (9)

Geometric parameters (Å, º)

Zn—O1W^i	2.063 (2)	C1—C2	1.380 (4)
Zn—O1W	2.063 (2)	C1—H1	0.9300
Zn—N1	2.107 (2)	C2—C3	1.378 (5)
Zn—N1^i	2.107 (2)	C2—H2	0.9300
Zn—O1^i	2.226 (2)	C3—C4	1.382 (4)
Zn—O1	2.226 (2)	C3—H3	0.9300
S—O1^ii	1.472 (2)	C4—C5	1.386 (4)
S—O1	1.472 (2)	C4—H4	0.9300
S—O2^ii	1.478 (2)	C5—C5^i	1.494 (5)
S—O2	1.478 (2)	O1W—H1WA	0.76 (2)
N1—C5	1.337 (3)	O1W—H1WB	0.76 (2)
N1—C1	1.343 (4)
O1W^i—Zn—O1W	95.25 (12)	C5—N1—C1	118.9 (2)
O1W^i—Zn—N1	169.26 (8)	C5—N1—Zn	115.98 (18)
O1W—Zn—N1	93.96 (9)	C1—N1—Zn	125.08 (19)
O1W^i—Zn—N1^i	93.96 (9)	N1—C1—C2	122.6 (3)
O1W—Zn—N1^i	169.26 (8)	N1—C1—H1	118.7
N1—Zn—N1^i	77.45 (12)	C2—C1—H1	118.7
O1W^i—Zn—O1^i	93.05 (9)	C3—C2—C1	118.4 (3)
O1W—Zn—O1^i	86.75 (8)	C3—C2—H2	120.8
N1—Zn—O1^i	92.97 (9)	C1—C2—H2	120.8
N1^i—Zn—O1^i	87.27 (8)	C2—C3—C4	119.5 (3)
O1W^i—Zn—O1	86.75 (8)	C2—C3—H3	120.3
O1W—Zn—O1	93.05 (9)	C4—C3—H3	120.3
N1—Zn—O1	87.27 (8)	C3—C4—C5	119.0 (3)
N1^i—Zn—O1	92.97 (9)	C3—C4—H4	120.5
O1^i—Zn—O1	179.69 (10)	C5—C4—H4	120.5
O1^ii—S—O1	109.74 (17)	N1—C5—C4	121.7 (2)
O1^ii—S—O2^ii	110.12 (13)	N1—C5—C5^i	115.29 (15)
O1—S—O2^ii	108.87 (11)	C4—C5—C5^i	123.03 (16)
O1^ii—S—O2	108.87 (11)	Zn—O1W—H1WA	97 (3)
O1—S—O2	110.12 (13)	Zn—O1W—H1WB	114 (3)
O2^ii—S—O2	109.11 (17)	H1WA—O1W—H1WB	108 (2)
S—O1—Zn	137.19 (12)

Symmetry codes: (i) −x, y, −z+1/2; (ii) −x, y, −z−1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O2^iii	0.76 (2)	1.90 (3)	2.658 (3)	177 (3)
O1W—H1WB···O2^iv	0.76 (3)	1.98 (3)	2.714 (3)	165 (3)

Symmetry codes: (iii) x, y, z+1; (iv) x, −y+1, z+1/2.