Poly[di-μ-chlorido-μ-(1,2,3,9-tetra­hydro­pyrrolo­[2,1-b]quinazolin-9-one-κ2N:O)-mercury(II)]

Turgunov, K.K.; Wang, Y.; Englert, U.; Shakhidoyatov, K.M.

doi:10.1107/S1600536811022471

metal-organic compounds

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Volume 67| Part 7| July 2011| Pages m953-m954

doi:10.1107/S1600536811022471

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Poly[di-μ-chlorido-μ-(1,2,3,9-tetrahydropyrrolo[2,1-b]quinazolin-9-one-κ²N:O)-mercury(II)]

Kambarali K. Turgunov,^a ^* Yutian Wang,^b Ulli Englert ^b and Khusnutdin M. Shakhidoyatov ^a

^aS. Yunusov Institute of the Chemistry of Plant Substances, Academy of Sciences of Uzbekistan, Mirzo Ulugbek Str. 77, Tashkent 100170, Uzbekistan, and ^bInstitute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
^*Correspondence e-mail: kk_turgunov@rambler.ru

(Received 24 May 2011; accepted 10 June 2011; online 18 June 2011)

In the crystal structure of the title two-dimensional network, [HgCl₂(C₁₁H₁₀N₂O)]_n, the asymmetric unit consists of HgCl₂ dumbbells and one molecule of the quinazoline unit. Pseudo-octahedrally coordinated Hg^II cations are chloride-bridged via a crystallographic inversion centre leading to different Hg—Cl bonds (short and long) and linked by other Cl atoms via translation along the a axis. The quinazoline ligands connect the Hg—Cl—Hg—Cl chains by N and O atoms along the b axis, forming the two-dimensional network structure. The crystal structure is stabilized by weak non-classical C—H⋯Cl hydrogen bonds and aromatic π–π stacking interactions [centroid–centroid distances = 3.942 (4) and 3.621 (4) Å].

Related literature

For the synthesis of the ligand, see: Chatterjee & Ganguly (1968 ). For the crystal structure of the ligand, see: Turgunov et al. (1995 ). For the crystal structure of the pure octahedral Hg^II ion and halide-bridged complex, see: Hu et al. (2007 ). For the crystal structure of a Hg^II complex with asymmetric Hg—Cl bonds, see: Batten et al. (2002 ); Hu et al. (2007); Merkens et al. (2010 ). For a general review of halide-bridged chain and crosslinking polymers, see: Englert (2010 ).

Experimental

Crystal data

[HgCl₂(C₁₁H₁₀N₂O)]
M_r = 457.70
Monoclinic, P 2₁ /n
a = 7.7275 (11) Å
b = 9.4705 (13) Å
c = 16.729 (2) Å
β = 101.416 (2)°
V = 1200.1 (3) Å³
Z = 4
Mo Kα radiation
μ = 13.25 mm⁻¹
T = 130 K
0.21 × 0.09 × 0.08 mm

Data collection

Bruker SMART APEX diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.167, T_max = 0.417
13274 measured reflections
3014 independent reflections
2620 reflections with I > 2σ(I)
R_int = 0.041

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.099
S = 1.20
3014 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 6.57 e Å⁻³
Δρ_min = −1.26 e Å⁻³

Table 1
Selected bond lengths (Å)

Hg1—Cl1	2.3258 (16)
Hg1—Cl2	2.3302 (16)
Hg1—Cl1ⁱ	3.1301 (16)
Hg1—Cl2ⁱⁱ	3.0416 (16)
Hg1—O1ⁱⁱⁱ	2.775 (6)
Hg1—N1	2.649 (6)
Symmetry codes: (i) -x+2, -y, -z; (ii) -x+1, -y, -z; (iii) x, y-1, z.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5A⋯Cl1^iv	0.93	2.81	3.630 (8)	147
C10—H10B⋯Cl2^v	0.97	2.76	3.724 (9)	171
Symmetry codes: (iv) -x+2, -y+1, -z; (v) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: SMART APEX (Bruker, 2000 ); cell refinement: SAINT-Plus (Bruker, 1999 ); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Bruker, 1998 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811022471/si2358sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811022471/si2358Isup2.hkl

checkCIF report

Comment top

The title compound represents the first crystal structure of a complex with the heterocyclic ligand 1,2,3,9-tetrahydropyrrolo(2,1 - b)quinazolin-9-one; the uncoordinated organic molecule has been reported by Turgunov et al. (1995).

The asymmetric unit contains a slightly bent HgCl₂ moiety (Cl1—Hg1—Cl2 = 171.44 (6)°) and one ligand molecule (Fig.1) In the crystal each Hg^II cation is coordinated by four bridging chlorido ligands in the equatorial plane; one N- and one O-connected organic ligand occupy the axial positions of a distorted octahedron. The Hg—Cl bonds are asymmetric with two short and two longer distances (Table 1).

The bridging chlorido ligands form zigzag Hg—Cl—Hg—Cl ring chains in the direction of the shortest lattice parameter. Strongly asymmetric halide bridges are well established structural features in the coordination chemistry of divalent mercury (Batten et al., 2002; Hu et al., 2007; Merkens et al., 2010; Englert, 2010).

The chlorido-bridged Hg···Hg distances amount to 3.9342 (7) and 3.9442 (7) Å. As the result of halide bridging in the [100] and bridging of the ditopic organic ligand in the [010] direction, an overall two-dimensional sheet is formed which is depicted in Fig. 2.

The observed structure is stabilized by weak C—H···Cl hydrogen bonds (Table 2). Cooperative π–π stacking interactions between neighbouring quinazolone ring systems also contribute to the stability of this layer structure (Cg1···Cg1ⁱ=3.942 (4) Cg1···Cg2ⁱ=3.621 (4) Å, where Cg1 represents the centroid of the pyrimidinone and Cg2 that of the benzo ring centroid, (i): 2 - x,1 - y,-z).

The ligand molecule is essentially planar with a maximum deviation of 0.044 (7) Å for atom C10 and an r.m.s. deviation of 0.015 Å.

Related literature top

For the synthesis of the ligand, see Chatterjee et al. (1968). For the crystal structure of the ligand, see Turgunov et al. (1995). For the crystal structure of the pure octahedral Hg^II ion and halide- bridged complex, see Hu et al. (2007). For the crystal structure of a Hg^II complex with asymmetric Hg—Cl bonds, see Batten et al. (2002); Hu et al. (2007); Merkens et al. (2010). For a general review of halide-bridged chain and crosslinking polymers, see Englert (2010).

Experimental top

A solution of 27.15 mg (0.1 mmol) of mercury (II) chloride in 2 ml water was added to a solution of 18.62 mg (0.1 mmol) of 1,2,3,9-tetrahydropyrrolo(2,1 - b)quinazolin-9-one in 2 ml acetone. The solution was allowed for slow evaporation at the room temperature. Colourless needle shaped crystals were obtained after several days.

Computing details top

Data collection: SMART APEX (Bruker, 2000); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Bruker, 1998); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The asymmetric unit of the title coordination polymer (50% displacement ellipsoids).
	Fig. 2. View of a single two-dimensional sheet. (Hydrogen atoms are omitted for clarity).

Poly[di-µ-chlorido-µ-(1,2,3,9-tetrahydropyrrolo[2,1-b]quinazolin- 9-one-κ²N:O)-mercury(II)] top

Crystal data top

[HgCl₂(C₁₁H₁₀N₂O)]	F(000) = 848
M_r = 457.70	D_x = 2.533 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3815 reflections
a = 7.7275 (11) Å	θ = 2.2–28.3°
b = 9.4705 (13) Å	µ = 13.25 mm⁻¹
c = 16.729 (2) Å	T = 130 K
β = 101.416 (2)°	Rod, colourless
V = 1200.1 (3) Å³	0.21 × 0.09 × 0.08 mm
Z = 4

Data collection top

Bruker SMART APEX diffractometer	3014 independent reflections
Radiation source: fine-focus sealed tube	2620 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.041
ω scans	θ_max = 28.5°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.167, T_max = 0.417	k = −12→12
13274 measured reflections	l = −22→22

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.099	H-atom parameters constrained
S = 1.20	w = 1/[σ²(F_o²) + (0.0432P)² + 2.8193P] where P = (F_o² + 2F_c²)/3
3014 reflections	(Δ/σ)_max = 0.001
154 parameters	Δρ_max = 6.57 e Å⁻³
0 restraints	Δρ_min = −1.26 e Å⁻³

Crystal data top

[HgCl₂(C₁₁H₁₀N₂O)]	V = 1200.1 (3) Å³
M_r = 457.70	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.7275 (11) Å	µ = 13.25 mm⁻¹
b = 9.4705 (13) Å	T = 130 K
c = 16.729 (2) Å	0.21 × 0.09 × 0.08 mm
β = 101.416 (2)°

Data collection top

Bruker SMART APEX diffractometer	3014 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2620 reflections with I > 2σ(I)
T_min = 0.167, T_max = 0.417	R_int = 0.041
13274 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.099	H-atom parameters constrained
S = 1.20	Δρ_max = 6.57 e Å⁻³
3014 reflections	Δρ_min = −1.26 e Å⁻³
154 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

	x	y	z	U_iso*/U_eq
Hg1	0.75260 (3)	0.03946 (3)	0.005310 (12)	0.02475 (11)
Cl1	0.9924 (2)	0.02655 (19)	0.11378 (9)	0.0277 (3)
Cl2	0.5237 (2)	0.01819 (19)	−0.10788 (9)	0.0288 (4)
O1	0.7419 (7)	0.7485 (6)	0.0235 (3)	0.0439 (14)
N1	0.7546 (6)	0.3191 (7)	0.0057 (3)	0.0248 (12)
C2	0.7279 (8)	0.3824 (8)	0.0697 (4)	0.0264 (14)
N3	0.7223 (7)	0.5265 (6)	0.0757 (3)	0.0245 (12)
C4	0.7484 (8)	0.6201 (8)	0.0148 (4)	0.0286 (14)
C4A	0.7784 (9)	0.5509 (7)	−0.0581 (4)	0.0238 (14)
C5	0.8068 (9)	0.6256 (8)	−0.1257 (4)	0.0320 (15)
H5A	0.8074	0.7237	−0.1240	0.038*
C6	0.8339 (9)	0.5600 (8)	−0.1943 (4)	0.0321 (16)
H6A	0.8510	0.6123	−0.2391	0.038*
C7	0.8355 (9)	0.4115 (7)	−0.1964 (4)	0.0249 (13)
H7A	0.8534	0.3659	−0.2434	0.030*
C8	0.8111 (8)	0.3315 (7)	−0.1301 (4)	0.0249 (13)
H8A	0.8143	0.2334	−0.1320	0.030*
C8A	0.7813 (8)	0.4016 (7)	−0.0596 (3)	0.0193 (12)
C9	0.6954 (10)	0.3200 (9)	0.1470 (4)	0.0374 (18)
H9A	0.7924	0.2592	0.1716	0.045*
H9B	0.5870	0.2654	0.1373	0.045*
C10	0.6806 (13)	0.4488 (10)	0.2024 (5)	0.049 (2)
H10A	0.5692	0.4460	0.2208	0.059*
H10B	0.7757	0.4470	0.2499	0.059*
C11	0.6914 (10)	0.5786 (8)	0.1545 (4)	0.0337 (17)
H11A	0.5822	0.6319	0.1475	0.040*
H11B	0.7880	0.6382	0.1810	0.040*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Hg1	0.02197 (15)	0.03650 (19)	0.01675 (14)	0.00429 (11)	0.00622 (9)	0.00185 (9)
Cl1	0.0231 (7)	0.0420 (10)	0.0188 (7)	0.0049 (7)	0.0060 (5)	0.0053 (6)
Cl2	0.0229 (8)	0.0452 (10)	0.0189 (7)	−0.0008 (7)	0.0055 (6)	0.0021 (6)
O1	0.059 (4)	0.035 (3)	0.043 (3)	0.009 (3)	0.021 (3)	−0.011 (3)
N1	0.028 (3)	0.031 (3)	0.016 (2)	0.005 (2)	0.005 (2)	−0.0025 (19)
C2	0.024 (3)	0.036 (4)	0.019 (3)	0.009 (3)	0.005 (2)	0.003 (3)
N3	0.021 (3)	0.033 (3)	0.020 (2)	0.011 (2)	0.004 (2)	−0.002 (2)
C4	0.023 (3)	0.035 (4)	0.029 (3)	0.004 (3)	0.007 (2)	−0.004 (3)
C4A	0.021 (3)	0.026 (4)	0.023 (3)	0.008 (3)	0.000 (2)	−0.002 (2)
C5	0.035 (4)	0.031 (4)	0.029 (3)	−0.001 (3)	0.005 (3)	0.005 (3)
C6	0.033 (4)	0.041 (5)	0.024 (3)	0.001 (3)	0.008 (3)	0.009 (3)
C7	0.026 (3)	0.031 (4)	0.018 (3)	0.001 (3)	0.006 (2)	−0.001 (2)
C8	0.027 (3)	0.025 (3)	0.022 (3)	0.005 (3)	0.005 (2)	0.000 (2)
C8A	0.017 (3)	0.023 (3)	0.017 (2)	0.004 (2)	0.000 (2)	0.002 (2)
C9	0.044 (4)	0.052 (5)	0.021 (3)	0.014 (4)	0.019 (3)	0.004 (3)
C10	0.057 (5)	0.069 (7)	0.023 (3)	−0.021 (5)	0.014 (3)	−0.016 (4)
C11	0.030 (4)	0.047 (5)	0.027 (3)	0.010 (3)	0.011 (3)	−0.014 (3)

Geometric parameters (Å, º) top

Hg1—Cl1	2.3258 (16)	C5—C6	1.357 (10)
Hg1—Cl2	2.3302 (16)	C5—H5A	0.93
Hg1—Cl1ⁱ	3.1301 (16)	C6—C7	1.407 (10)
Hg1—Cl2ⁱⁱ	3.0416 (16)	C6—H6A	0.93
Hg1—O1ⁱⁱⁱ	2.775 (6)	C7—C8	1.387 (9)
Hg1—N1	2.649 (6)	C7—H7A	0.93
O1—C4	1.227 (9)	C8—C8A	1.411 (8)
N1—C2	1.279 (8)	C8—H8A	0.93
N1—C8A	1.392 (8)	C9—C10	1.550 (11)
C2—N3	1.370 (9)	C9—H9A	0.97
C2—C9	1.488 (9)	C9—H9B	0.97
N3—C4	1.395 (9)	C10—C11	1.479 (12)
N3—C11	1.471 (8)	C10—H10A	0.97
C4—C4A	1.442 (9)	C10—H10B	0.97
C4A—C5	1.388 (9)	C11—H11A	0.97
C4A—C8A	1.415 (10)	C11—H11B	0.97

Cl1—Hg1—Cl2	171.44 (7)	C6—C7—H7A	119.3
Cl1—Hg1—N1	92.70 (11)	C7—C8—C8A	118.8 (6)
Cl2—Hg1—N1	95.27 (11)	C7—C8—H8A	120.6
C2—N1—C8A	117.9 (6)	C8A—C8—H8A	120.6
C2—N1—Hg1	118.0 (5)	N1—C8A—C8	117.8 (6)
C8A—N1—Hg1	124.1 (4)	N1—C8A—C4A	122.8 (5)
N1—C2—N3	122.7 (6)	C8—C8A—C4A	119.4 (5)
N1—C2—C9	128.6 (7)	C2—C9—C10	104.6 (7)
N3—C2—C9	108.6 (5)	C2—C9—H9A	110.8
C2—N3—C4	124.6 (5)	C10—C9—H9A	110.8
C2—N3—C11	114.4 (5)	C2—C9—H9B	110.8
C4—N3—C11	121.0 (6)	C10—C9—H9B	110.8
O1—C4—N3	121.9 (6)	H9A—C9—H9B	108.9
O1—C4—C4A	124.6 (7)	C11—C10—C9	108.1 (6)
N3—C4—C4A	113.6 (6)	C11—C10—H10A	110.1
C5—C4A—C8A	119.2 (6)	C9—C10—H10A	110.1
C5—C4A—C4	122.4 (7)	C11—C10—H10B	110.1
C8A—C4A—C4	118.3 (6)	C9—C10—H10B	110.1
C6—C5—C4A	122.1 (7)	H10A—C10—H10B	108.4
C6—C5—H5A	118.9	N3—C11—C10	104.1 (6)
C4A—C5—H5A	118.9	N3—C11—H11A	110.9
C5—C6—C7	118.9 (6)	C10—C11—H11A	110.9
C5—C6—H6A	120.6	N3—C11—H11B	110.9
C7—C6—H6A	120.6	C10—C11—H11B	110.9
C8—C7—C6	121.4 (6)	H11A—C11—H11B	109.0
C8—C7—H7A	119.3

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5A···Cl1^iv	0.93	2.81	3.630 (8)	147
C10—H10B···Cl2^v	0.97	2.76	3.724 (9)	171

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

Experimental details

Crystal data
Chemical formula	[HgCl₂(C₁₁H₁₀N₂O)]
M_r	457.70
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	130
a, b, c (Å)	7.7275 (11), 9.4705 (13), 16.729 (2)
β (°)	101.416 (2)
V (Å³)	1200.1 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	13.25
Crystal size (mm)	0.21 × 0.09 × 0.08

Data collection
Diffractometer	Bruker SMART APEX diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.167, 0.417
No. of measured, independent and observed [I > 2σ(I)] reflections	13274, 3014, 2620
R_int	0.041
(sin θ/λ)_max (Å⁻¹)	0.671

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.099, 1.20
No. of reflections	3014
No. of parameters	154
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	6.57, −1.26

Computer programs: SMART APEX (Bruker, 2000), SAINT-Plus (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP (Bruker, 1998), publCIF (Westrip, 2010).

Selected bond lengths (Å) top

Hg1—Cl1	2.3258 (16)	Hg1—Cl2ⁱⁱ	3.0416 (16)
Hg1—Cl2	2.3302 (16)	Hg1—O1ⁱⁱⁱ	2.775 (6)
Hg1—Cl1ⁱ	3.1301 (16)	Hg1—N1	2.649 (6)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5A···Cl1^iv	0.93	2.81	3.630 (8)	147.0
C10—H10B···Cl2^v	0.97	2.76	3.724 (9)	171.0

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

Acknowledgements

The authors gratefully acknowledge the DAAD for supporting this study.

References

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