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Article

[AuHg(o-C6H4PPh2)2I]: A Dinuclear Heterometallic Blue Emitter

by
José M. López-de-Luzuriaga
*,
Miguel Monge
,
M. Elena Olmos
and
David Pascual
Departamento de Química, Universidad de La Rioja. Centro de Investigación en Síntesis Química (CISQ), Complejo Científico-Tecnológico, 26004-Logroño, Spain
*
Author to whom correspondence should be addressed.
Inorganics 2015, 3(1), 27-39; https://doi.org/10.3390/inorganics3010027
Submission received: 15 December 2014 / Accepted: 3 February 2015 / Published: 11 February 2015
(This article belongs to the Special Issue Frontiers in Gold Chemistry)
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Abstract

:
The heteronuclear AuI/HgII complex [AuHg(o-C6H4PPh2)2I] (1) was prepared by reacting of [Hg(2-C6H4PPh2)2] with [Au(tht)2]ClO4 (1:1) and NaI in excess. The heterometallic compound 1 has been structurally characterized and shows an unusual blue luminescent emission in the solid state. Theoretical calculations suggest that that the origin of the emission arises from the iodide ligand arriving at metal-based orbitals in a Ligand to Metal-Metal Charge Transfer transition.

1. Introduction

Complexes with metallophilic interactions have been the subjects of intense research in the last few years. The interest in this type of complexes covers several areas of research, including, among others, supramolecular structural analysis or theoretical calculations on the nature of the metallophilic interactions [1,2,3,4]. Furthermore, the complexes that present these interactions, usually exhibit interesting photoluminescent or vapochromic properties of relevance for applications in luminescence signaling and vapochemical sensing [5,6,7].
Regarding this topic, our research group has been devoted to the synthesis of new compounds bearing metallophilic interactions between heavy closed shell metal ions, with gold occupying a preferential position among them. Thus, we have succeeded in synthesizing a number of complexes displaying interactions between gold(I) and other closed shell metal centers. The synthetic and theoretical study of this type of interactions is still nowadays a challenge because of their implications in the structure and properties of the complexes that contain them. Thus, we have described complexes with d10-d10 interactions between AuI and their group congeners AgI or CuI [8,9,10,11,12,13]; d10-d8 interactions as, for instance, those appearing in the complexes [Hg{Au(C6F5)Cl2(μ-2-C6H4PPh2)}2] or [{AuCl(Ph2PCH2SPh)}2PdCl2] [14,15]; or with post-transition metals as TlI, SnII or BiIII, in which the interactions are of the type d10-s2. [16,17,18] In addition, very recently, we reported the synthesis of complexes displaying unsupported AuI-HgII interactions, that in addition to their interesting structural characteristics show fascinating luminescent properties or even the capability to quench very effectively the emission of organic molecules [19,20].
Regarding the luminescent properties, from a practical viewpoint, the greater efforts are oriented to obtain blue emissive compounds. However, the number of heterometallic compounds that emit in the blue range is still comparatively very scarce. For instance, in our case, from all the complexes studied only in the case of the complexes [{AuTl(C6Cl5)2(toluene)}2(dioxane)], {[Tl(η6-toluene)][Au(C6Cl5)2]}, [{Au(C6Cl5)2}Ag([14]aneS4)] or [{Au(C6F5)2}Tl([14]aneS4)]2 present this color in their emissions [21,22,23]. From our studies we have concluded that one of the conditions that must be met to obtain blue luminescent compounds is that their molecular structures must consist preferably of discrete units instead of the most common extended 1-D, 2-D, or even 3-D structures. The main reason is that the structures in which the dimensionality is built by metallophilic contacts, the luminescence is usually based in metal centered emissions, and the polymeric nature of these species provokes the delocalization of the exciton along the chains of metals, a lower HOMO-LUMO gap and, therefore, low energy emissions. Consequently, molecules displaying intermetallic interactions, but with lower dimensionality, should present higher energy emissions.
Thus, in this paper we report the synthesis and characterization of the complex [AuHg(o-C6H4PPh2)2I] (1), whose molecular nature in solid state and in solution permits it to behave as a blue emitter. In addition, in this paper we describe its photophysical properties and a theoretical interpretation of the excited state properties by mean of MP2 calculations.

2. Results and Discussion

2.1. Synthesis and Characterization

The synthetic strategy in this case consisted of the use of a metal precursor bearing unsaturated donor centers and its reaction with a metal atom coordinated to labile ligands, with the simultaneous presence of an anion with affinity for one of the metal centers. With these conditions we hinder the polymerization by intermetallic contacts between different molecules by blocking one position.
Thus, the reaction of [Hg(o-C6H4PPh2)2] with an equimolecular amount of [Au(tht)2]ClO4 in dichloromethane and an excess of an aqueous solution of NaI produces the coordination of the gold center to the phosphine ligands by displacement of the tht ligands and simultaneous substitution of the ClO4− anion by I−, forming the complex [AuHg(o-C6H4PPh2)2I] (1) (See Scheme 1). The electrospray (−) high-resolution mass spectrum of 1 shows a peak that corresponds to the anion I− at m/z = 126.90. In addition, the signal corresponding to the cation [AuHg(o-C6H4PPh2)2]+ also appears in its electrospray (+) spectrum at m/z = 921.11. The 31P{1H} NMR spectrum of 1 in CDCl3 shows a unique singlet at δ = 39.9 ppm, indicating the magnetic equivalence of both phosphorous atoms present in this complex, as well as the coordination of the phosphine ligands to the gold center in solution due to the deshielding of the original position at −1.8 ppm in the starting mercury derivative [Hg(o-C6H4PPh2)2]. Interestingly, the conductivity measurement of complex 1 in dichloromethane solution gives a value of 0.1 Ω−1·cm2·mol−1, indicating that the iodine anion, instead of dissociating in solution, is bonded to a metal center. The remaining analytical and spectroscopic data are in accordance with the proposed structure (see Experimental Section).
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Scheme 1. Synthesis of complex 1.
Scheme 1. Synthesis of complex 1.
Inorganics 03 00027 g005

2.2. Crystal Structure

The crystal structure of [AuHg(o-C6H4PPh2)2I]·CH2Cl2 (1) was determined by X-ray diffraction from single crystals obtained by slow diffusion of n-hexane into a solution of the complex in dichloromethane. Compound 1 crystallizes in the monoclinic space group P21/a with a molecule of CH2Cl2 per molecule of compound.
The crystal structure of [AuHg(o-C6H4PPh2)2I]·CH2Cl2 (1) shows an eight-member dimetallacycle in a twisted conformation, which is formed by both metal atoms and two PC2 fragments of the bridging ligands in a head-to-head disposition with Au-P and Hg-C bonds (see Figure 1). Additionally, a iodine atom is bonded to the gold center with a Au-I bond distance of 2.8998(3) Å, lying within the range 2.8052(4)–3.0831(7) Å, observed for other related dinuclear gold(I) species of the type [Au2(μ-diphosphine)2I2] containing three-coordinated gold(I) atoms [24,25,26,27], and identical to that found in α-Au2(μ-dppe)2I2·2OCMe2 (2.906(2) Å) [24]. The gold center binds to both phosphorus with Au-P bond distances of 2.3295(11) and 2.3323(11) Å, which compare well with most of the Au-P bond lengths described for the related complexes cited above (2.2997(6)–2.342(3) Å) [24,25,26,27]. The crystal structure of 1 reveals a distorted T-shaped geometry at the gold atom if the intermetallic interaction is not considered. Although the P-Au-P angle shows a marked deviation from linearity (P-Au-P = 154.28(4)°), the AuP2I unit is planar, with a sum of the two P-Au-I angles and the P-Au-P one of 359.94°. Similar situations have been found in [Au2(μ-PPh2(CH2)3PPh2)2]I2 [25] or in [Au2(dcpm)2]I2 (dcpm = bis(dicyclohexylphosphino)methane) [27], which show P-Au-P angles of 157.93(7) or 152.88(3)°, respectively, and a planar three-coordinate environment for AuI. The intermetallic distance of 3.0943(2) Å, shorter than the sum of the Van der Waals radii of gold and mercury (3.21 Å) [28], evidences the presence of a AuI···HgII contact. This value is intermediate between the maximum and minimum Au-Hg distances found in the literature for other complexes displaying supported Au···Hg interactions: [HgAu(CH2SPPh2CH2)2]PF6 (2.934(1) Å) [29]; [AuHg(Cl)2(o-C6H4PPh2)] (3.112(1) Å) [30]; [HgAu(SPPh2CH2)2]PF6 (3.079(2) Å) [31]; or [Hg(CH2P(S)PPh2)2(AuCl)2] (3.310(1) Å) [31]. Finally, the mercury(II) center is nearly linearly coordinated to two carbon atoms (C-Hg-C = 175.46(17)°) showing typical Hg-C (2.090(4) and 2.096(4) Å) bond distances for an aryl-mercury(II) coordination. Taking into account the Au···Hg interaction, the coordination environment of mercury can be described as T-shape, since the intermetallic contact is orthogonal to the C-Hg-C axis (C-Hg-Au = 90.30(12) and 92.29(12)°) (see Table 1).
Inorganics 03 00027 g001 1024
Figure 1. Crystal structure of compound 1.Thermal ellipsoid are set at 35% probability.
Figure 1. Crystal structure of compound 1.Thermal ellipsoid are set at 35% probability.
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Table
Table 1. Selected bond lengths (Å) and angles (°) for complex 1.
Table 1. Selected bond lengths (Å) and angles (°) for complex 1.
Bond Distance (Å)/Angle(º)1
Au-Hg3.0944(2)
Au-P(1)2.3298(11)
Au-P(2)2.3323(11)
Au-I2.8997(3)
Hg-C(1)2.097(4)
Hg-C(11)2.090(4)
P(1)-Au-P(2)154.25(4)
I-Au-Hg163.150(9)
C(1)-Hg-C(11)175.47(16)

2.3. Photophysical Properties and Theoretical Calculations

Usually, complexes displaying Au(I)-M(I) (M = coinage metals) or Au(I)-Hg(II) interactions show emission lifetimes in the nanosecond range, and colors in the yellow-orange range of the visible spectrum, which was assigned to delocalized excitons in extended chains or two- or three-dimensional networks [8,9,10,11,12,13,19,20]. Only a few cases complexes behave as blue emitters and show longer (microsecond) lifetimes. These consist of discrete heterometallic units [21,22,23] or localized excitons in polynuclear systems. Complex 1 is an example of the latter. It shows an unusual blue luminescence at room temperature in solid state (λem. = 456 nm (λexc. = 367 nm)) and at 77K (λem. = 475 nm (λexc. = 363 nm)) (see Table 2), however, in dichloromethane solutions its emissive properties are lost. This fact can be due to the formation of non-luminescent exciplexes with solvent molecules in the excited state. The absorption spectrum in a 3 × 10−5 M CH2Cl2 solution shows a band centered at 236 nm (ε = 32920 M−1·cm−1) that is also present in the mercury precursor absorption spectrum (see Figure 2). This band can be tentatively assigned to a π-π* intraligand transition. Additionally, the spectrum of [AuHg(o-C6H4PPh2)2I] (1) shows a band of very low intensity at 357 nm (ε = 1246 M−1·cm−1) that is not present in the mercury precursor. This new band appears approximately at the same energy than the excitation (see inset of the Figure 2) and can be assigned to a spin forbidden S0→T1 transition. The lifetime in the microsecond range (1.57 μs) together with the large Stokes shift (5314 cm−1) suggest a phosphorescent emission.
Table
Table 2. Photophysical properties of [AuHg(o-C6H4PPh2)2I] (1).
Table 2. Photophysical properties of [AuHg(o-C6H4PPh2)2I] (1).
ComplexMedium (T [K])λabs [nm] (ε [M−1 cm−1])λem (λexc)[nm]/τ [μs]/]/Ф (%)
1CH2Cl2 (RT) 236(32920), 357(1246)-
Solid (RT) 456 (367)/1.57/27.6
Solid (77K) 475 (363)
Inorganics 03 00027 g002 1024
Figure 2. (a) UV-vis spectrum for complexes [Hg(o-C6H4PPh2)2] (red) and 1 (black) in dichloromethane solutions. (b) Normalized excitation (black) and emission (red) spectra in the solid state at RT (solid line) and emission at 77 K (dotted line) for complexes 1.
Figure 2. (a) UV-vis spectrum for complexes [Hg(o-C6H4PPh2)2] (red) and 1 (black) in dichloromethane solutions. (b) Normalized excitation (black) and emission (red) spectra in the solid state at RT (solid line) and emission at 77 K (dotted line) for complexes 1.
Inorganics 03 00027 g002
In view of the interesting photophysical properties displayed by this heterometallic Au(I)···Hg(II) complex we have carried out computational studies to deepen into the origin of this behavior. For this, we have carried out ab initio 2nd order Moller-Plesset (MP2) calculations on the dinuclear model system [AuHg(o-C6H4PH2)2I] (1a) (See Computational Details). This level of theory has been chosen since it has been repeatedly proven to reproduce the dispersive origin of the metallophilic interactions observed experimentally [2,3,4].
We have fully optimized model 1a without any symmetry constrains, both in the ground (S0) and lowest triplet excited state (T1). The ground state optimization of model 1a provides important information: first, the optimized structural parameters can be compared with the experimental ones, including the intermetallic closed-shell Au(I)···Hg(II) interaction distance, what permits to validate the level of theory chosen and, second, the shape of the highest occupied molecular orbital (HOMO) shows the part of the molecule from which the electronic excitation related to the photoluminescent behavior of this complex arises. On the other hand, the lowest triplet excited state (T1) structural optimization also provides interesting results: first, the structural distortions observed in the S0→T1 electronic excitation rely information about which part of the molecule would be involved in the experimentally observed phosphorescent transition and, second, the shape of the highest simply occupied molecular orbital (SOMO) to which the electron arrives in the S0→T1 excitation permits to confirm the origin of the emissive properties.
As is depicted in Table 3 the full optimization of model 1a in the S0 state shows similar structural parameters to the ones experimentally obtained for complex 1 through X-ray diffraction analysis. It is worth mentioning that the MP2 level of theory, which includes correlation effects, leads to a good agreement between the theoretically predicted and the experimentally obtained Au(I)···Hg(II) intermetallic distances (d(Au-Hg) = 3.05 (theor.) 3.09 Å (exp.)), and for the coordination environments of the metal centers. The slight deviation of the theoretically predicted Hg-Au-I angle (168.4°) with respect to the experimental one (176.2°) would be related with the fact that the theoretical model is calculated in the gas phase where packing effects are not considered. In the next step we have carried out the full optimization of the lowest triplet excited state (T1) for model 1a. This T1 state displays important structural distortions around the metal centers. The most important distortion consists of a large shortening of the intermetallic Au-Hg distance from 3.05 in the ground S0 state to 2.79 Å in the lowest triplet T1 state, leading to a very short metal-metal interaction. In contrast, an appreciable increase of the Au-P distances is observed, going from 2.35 (S0) to 2.46 Å (T1) (see Table 3 and Figure 3). The rest of bond distances obtained for model 1a in the T1 state only suffer slight changes with respect to the S0 state. Also, the P-Au-P angle bents outwards from 157.4° in the ground state to 168.5° in the lowest triplet excited state, pushing the Au(I) center closer to the Hg(II) one. Overall, since the T1 excited state distortions found for model 1a can be related to a main change of the Au(I) and Hg(II) coordination environments and, specially, a shortening of the Au(I)···Hg(II) metallophilic distance, the phosphorescent properties of this complex could be ascribed to a S0→T1 electronic transition involving these interacting closed-shell metals.
Another interesting result that can be derived from the full optimization of model 1a in the S0 and T1 states is the analysis of the frontier molecular orbitals (MOs) for each model systems. In a phosphorescent process we can attribute the origin of the emissive properties to an electronic transition between the HOMO (Highest Occupied Molecular Orbital) in the S0 ground state and the SOMO (Singly Occupied Molecular Orbital) in the T1 state. The frontier MOs for model 1a in the S0 (HOMO and LUMO) and T1 (SOMO and SOMO-1) states are depicted in Figure 4. The HOMO orbital in model 1a is mainly located at a 5p antibonding orbital of the iodide ligand with a small contribution of the gold center. On the other hand the SOMO is a 6s/6p bonding orbital to which the electron arrives in the S0→T1 electronic transition and that is mostly placed at the interacting Au(I)···Hg(II) closed-shell metal centers. It is worth mentioning that this bonding character of the SOMO orbital would be related to the Au-Hg distance shortening since a bond order increase between the metals would take place upon the electron excitation from the antibonding 5p orbital at the iodide ligand to the bonding 6s/6p metal-based bonding orbital. Therefore, in view of the shape of the HOMO and SOMO orbitals and, taking also into account the structural distortions described above for the T1 state with respect to the S0 one, we suggest that the origin of the phosphorescence for complex 1 is a forbidden Ligand to Metal-Metal Charge Transfer transition from the iodide ligand to the interacting Au(I)···Hg(II) metal centers 3(LMMCT).
Inorganics 03 00027 g003 1024
Figure 3. Fully optimized model system [AuHg(o-C6H4PH2)2I] (1a) in the ground (S0) (left) and the lowest triplet excited state (T1) (right).
Figure 3. Fully optimized model system [AuHg(o-C6H4PH2)2I] (1a) in the ground (S0) (left) and the lowest triplet excited state (T1) (right).
Inorganics 03 00027 g003
Table
Table 3. Selected experimental and theoretical distances (Å) and angles (°) for complex [AuHg(o-C6H4PPh2)2I] (1) and model [AuHg(o-C6H4PH2)2I] (1a) in the ground (S0) and excited (T1) states.
Table 3. Selected experimental and theoretical distances (Å) and angles (°) for complex [AuHg(o-C6H4PPh2)2I] (1) and model [AuHg(o-C6H4PH2)2I] (1a) in the ground (S0) and excited (T1) states.
Distances/AnglesExp. in 1S0 in 1aT1 in 1a
Au-Hg3.093.052.79
Au-P12.332.352.46
Au-P22.332.352.46
Au-I2.902.782.76
Hg-C12.102.132.13
Hg-C112.092.132.13
Hg-Au-I163.2180.0179.0
P1-Au-P2154.3157.4168.3
C1-Hg-C11175.5168.4170.5
Inorganics 03 00027 g004 1024
Figure 4. Frontier molecular orbitals for the model system 1a in the S0 and T1 states.
Figure 4. Frontier molecular orbitals for the model system 1a in the S0 and T1 states.
Inorganics 03 00027 g004

3. Experimental Section

3.1. General Considerations

All reactions were carried out under argon atmosphere using Schlenk techniques. All solvents were dry and deoxygenated. Solvents used in the spectroscopic studies were degassed prior to use. [Au(tht)2]ClO4 and [Hg(2-C6H4PPh2)2] were prepared according to literature methods [32,33]. Caution! Due to the toxicity of mercury compounds extra care was taken to avoid contact with solid, solution, and airborne mercury products.

3.2. Instrumentation

Carbon and hydrogen analyses were carried out with a Perkin-Elmer 240C microanalyzer. 1H and 31P{1H} NMR spectra were recorded on a Bruker Avance 400 in CDCl3 solutions. Chemical shifts are quoted relative to H3PO4 85% (31P external) and SiMe4 (1H, external). Mass spectra were recorded on a HP-5989B Mass Spectrometer API-Electrospray with interface 59987A. Absorption spectra in solution were registered on a Hewlett Packard 8453 Diode Array UV-visible spectrophotometer. Excitation and emission spectra were recorded on a Jobin-Yvon Horiba Fluorolog 3-22 Tau-3 spectrofluorimeter. Lifetime measurements were recorded with a Datastation HUB-B with a nanoLED controller and software DAS6 (version 6.3, ORIBA Jobin-Yvon Inc., Edison, NJ, USA). The nanoLED employed for lifetime measurements was of 371 nm with pulse lengths of 1.1 ns. The lifetime data were fitted using the Jobin-Yvon software package (version 3.1, ORIBA Jobin-Yvon Inc., Edison, NJ, USA).

3.3. Synthesis of [AuHg(o-C6H4PPh2)2I], 1

To a dichloromethane solution (30 mL) of [Hg(o-C6H4PPh2)2] (0.10 g, 0.13 mmol) was added an equimolecular amount of [Au(tht)2]ClO4 (0.06 g, 0.13 mmol)and an excess of an aqueous solution of NaI. The reaction mixture was stirred for 24 h at room temperature resulting in a colorless, clear aqueous layer and an orange, clear organic layer. The mixture is shaken in a separation funnel and the organic layer was separated and washed again with H2O (15 mL). Evaporation of the solvent under vacuum and addition of n-hexane gave rise to complex 1 as a brown solid. Yield: 76%. Elemental analyses (%) calcd for 1 (C36H28AuBrHgIP2): C 41.3, H 2.70. Found: C 41.5, H 2.77. 31P{1H} NMR (121.5 MHz, CDCl3, ppm): δ 39.9 (s, 2P). 1H NMR (400 MHz, CDCl3, ppm): δ 7.14–7.46 (m, 28H, aromatic). MS (ES+): m/z 921.11 [AuHg(o-C6H4PPh2)2]+, MS (ES-): m/z 126.90 [I]−.

3.4. X-ray Crystallography Details

The crystal was mounted in inert oil on glass fibers and transferred to the cold gas stream of a Nonius Kappa CCD diffractometer equipped with an Oxford Instruments low-temperature attachment. Data were collected using monochromated MoKa radiation (λ = 0.71073 Å). Scan type: ω and ϕ. Absorption correction: semiempirical (based on multiple scans). The structure was solved by Patterson and refined on F2 using the program SHELXL-97 [34]. All non-hydrogen atoms were refined anisotropically. Hydrogen atoms were included using a riding model. Graphics were prepared with Olex2 [35]. Further details of the data collection and refinement are given in Table 4. Selected bond lengths and angles are collected in Table 1; the crystal structure of complex 1 appears in Figure 1.
Table
Table 4. X-ray crystallographic data is shown for complex 1.
Table 4. X-ray crystallographic data is shown for complex 1.
ParameterCompound 1
FormulaC37 H30 Au Cl2 Hg I P2
Formula weight1131.91
Crystal habitColorless prism
Crystal size0.40 × 0.15 × 0.15 mm3
Crystal systemMonoclinic
Space groupP21/a
a/Å17.1928(4)
b/Å11.2469(3)
c/Å18.0925(4)
β/degβ 96.1080(10)
V/Å33478.61(15)
Z4
Dc/Mg·m−32.161
Mr9.780
F(000)2112
T/K173
θ range/deg3.90–27.60
No. rflns measd52126
No. unique rflns8039
Rint0.0585
Ra (I > 2σ(I)) 0.0278
Rwb (F2, all rflns)0.0377
Sc1.027
CCDC- 1037872 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/conts/retrieving.html (or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: (+44) 1223-336-033; or e-mail: [email protected]).

3.5. Computational Details

All calculations were carried out using the Gaussian 09 program package [36] at the MP2 level of theory [37,38].
Basis Sets. The 19-valence electron (VE) quasirelativistic (QR) pseudopotential (PP) of Andrae [39] was employed for gold together with two f-type polarization functions (exponents: 0.2, 1.19) [40]. Similarly, the 20-valence valence electron (VE) quasirelativistic (QR) pseudopotential (PP) of Andrae [39] was employed for mercury together with two f-type polarization functions (exponents: 0.545, 1.58) [41]. The atoms F, P, and C were treated by Stuttgart pseudopotentials [42], including only the valence electrons for each atom. For these atoms double-zeta basis sets of ref. [42] were used, augmented by d-type polarization functions [43]. For the H atom, a double-zeta, plus a p-type polarization function was used [44].

4. Conclusions

The use of asymmetric C,P-bidentate ligands allows the synthesis of a heterometallic gold(I)-mercury(II) complex showing a dinuclear arrangement including metallophilic Au(I)···Hg(II) interactions. These are responsible for an intense blue luminesce in solid state assigned to a Charge Transfer transition from the iodide ligand to metal-based orbitals according to experimental and theoretical ab-initio studies.

Acknowledgments

This work was supported by the DGI Project (MEC)/FEDER (project number CTQ2013-48635-C2-2-P). The Centro de Supercomputación de Galicia (CESGA) is acknowledged for computational resources. D. Pascual thanks the CAR for a grant.

Author Contributions

JML-de-L, MM, MEO and DP conceived and designed the experiments, performed the experiments, analyzed the data and wrote the paper.

Conflicts of Interest

The authors declare no conflict of interest.

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MDPI and ACS Style

López-de-Luzuriaga, J.M.; Monge, M.; Olmos, M.E.; Pascual, D. [AuHg(o-C6H4PPh2)2I]: A Dinuclear Heterometallic Blue Emitter. Inorganics 2015, 3, 27-39. https://doi.org/10.3390/inorganics3010027

AMA Style

López-de-Luzuriaga JM, Monge M, Olmos ME, Pascual D. [AuHg(o-C6H4PPh2)2I]: A Dinuclear Heterometallic Blue Emitter. Inorganics. 2015; 3(1):27-39. https://doi.org/10.3390/inorganics3010027

Chicago/Turabian Style

López-de-Luzuriaga, José M., Miguel Monge, M. Elena Olmos, and David Pascual. 2015. "[AuHg(o-C6H4PPh2)2I]: A Dinuclear Heterometallic Blue Emitter" Inorganics 3, no. 1: 27-39. https://doi.org/10.3390/inorganics3010027

APA Style

López-de-Luzuriaga, J. M., Monge, M., Olmos, M. E., & Pascual, D. (2015). [AuHg(o-C6H4PPh2)2I]: A Dinuclear Heterometallic Blue Emitter. Inorganics, 3(1), 27-39. https://doi.org/10.3390/inorganics3010027

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