Syntheses and Characterization of Two Dicyanamide Compounds Containing Monovalent Cations: Hg2[N(CN)2]2 and Tl[N(CN)2]
1
Chair of Solid-State and Quantum Chemistry, Institute of Inorganic Chemistry, RWTH Aachen University, 52056 Aachen, Germany
2
Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
*
Author to whom correspondence should be addressed.
Inorganics 2018, 6(4), 135; https://doi.org/10.3390/inorganics6040135
Submission received: 6 December 2018
/
Revised: 12 December 2018
/
Accepted: 13 December 2018
/
Published: 18 December 2018
(This article belongs to the Section Inorganic Solid-State Chemistry)
Abstract
:Crystals of Hg2[N(CN)2]2 were grown by a slow diffusion-reaction between aqueous Hg2(NO3)2·2H2O and Na[N(CN)2]. Hg2[N(CN)2]2 adopts the triclinic space group P (no. 2) with a = 3.7089(5), b = 6.4098(6), c = 8.150(6) Å, α = 81.575(6)°, β = 80.379(7)°, γ = 80.195(7)°, and Z = 1. Crystals of Tl[N(CN)2] were obtained from the reaction of TlBr with Ag[N(CN)2] in water. Single-crystal structure analyses evidence that Tl[N(CN)2] is isotypic to α-K[N(CN)2] and adopts the orthorhombic space group Pbcm (no. 57) with a = 8.5770(17), b = 6.4756(13), c = 7.2306(14) Å, and Z = 4. Regarding volume chemistry, the dicyanamide anion occupies ca. 44 cm3·mol−1, and so it corresponds to a large pseudohalide. The IR spectra of both compounds exhibit vibrational modes that are characteristic of the dicyanamide anion.
Keywords:
dicyanamide; mercury; thallium; crystal structure; volume chemistry; IR spectrum; metathesis
1. Introduction
Nitrogen-based solid-state materials have found extremely diverse applications, for example, as simple fertilizers, as high-performance steel coatings, as III-V optical semiconductors, and, quite recently, even as lithium- and sodium-ion battery materials. In particular, complex nitrogen containing compounds beyond the simple, yet fundamental nitrides, such as carbodiimides or guanidinates, are promising materials [1,2,3]. Similar to the latter in terms of chemical functionality, another interesting inorganic moiety is the boomerang-shaped dicyanamide anion [N(CN)2]−, which is often dubbed as [dca]−. It is intriguing, since it possesses one doubly-coordinated and two singly-coordinated nitrogen atoms plus several electron lone pairs.
Generally speaking, the solubility of a metal dicyanamide in water is an important factor regarding the synthetic strategy of whatever binary or ternary phase is targeted. If the desired product is insoluble in water and can be filtered off after a metathesis reaction with Na[dca], therefore this method can be used to grow crystals via a diffusion reaction. If the target compound is water soluble, however, it can be synthesized employing a metathesis reaction with Ag[dca]. In this case, the driving force for the reaction is the subsequent formation of insoluble silver halides. After filtering to remove the silver halides, the product can then be crystallized by simply evaporating water. Binary dicyanamide compounds are known for ammonium [4], alkali metals [5,6,7,8] (except Fr), alkaline-earth metals [9] (except Be and Ra), transition metals (Cr–Zn, except Fe) [10,11,12,13,14,15,16], and rare-earth metals (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb) [17,18,19]. Ternary compounds, such as KCs[dca]2 [20], LiK[dca]2 [21], LiRb[dca]2 [21], NaRb2[dca]3∙H2O [20], NaCs2[dca]3 [22], and LiCs2[dca]3 [23] are also known.
The synthesis of Hg2[dca]2 from Hg2(NO3)2 with Na[dca] has been reported almost a century ago [24], but no structural characterization was performed. Another attempt to characterize Hg2[dca]2 by Kuhn and Mecke [25] in 1961 was based on IR data on a number of different dicyanamides. These measurements provided valid proof that the shape of the dicyanamide anion is kinked (or boomerang-shaped) instead of linear. Even though a working synthesis was known, no further investigations were made regarding the crystal structure of Hg2[dca]2. A further dicyanamide compound containing a monovalent cation with unknown crystal structure is Tl[dca]. Because of its high solubility in water, Tl[dca] cannot be synthesized analogously to Hg2[dca]2. The use of Ag[dca] provides a convenient alternative route to the crystals of Tl[dca]. We here report the syntheses and single-crystal structure determinations of Hg2[dca]2 and Tl[dca].
2. Results and Discussion
2.1. Structural Description and Discussion
Hg2[N(CN)2]2 adopts the triclinic space group P (no. 2) with a = 3.7089(5), b = 6.4098(6), c = 8.150(6) Å, α = 81.575(6)°, β = 80.379(7)°, γ = 80.195(7)°, and Z = 1. Similar to most Hg(I) compounds, crystalline Hg2[N(CN)2]2 contains Hg2 moieties with d(Hg–Hg) = 2.518(3) Å. The structure can be compared to that of calomel, Hg2Cl2, where d(Hg–Hg) = 2.53 Å [26]. In Hg2[dca]2, every Hg2 dumbbell is bonded to two [dca] anions forming a quasi-molecular Hg2[dca]2 unit (Figure 1). A distorted octahedral coordination results for each Hg(I) due to four more coordinating nitrogen atoms. Therefore, every Hg(I) is surrounded by a total of five nitrogen belonging to five different [dca] anions, and also by the neighboring Hg(I) ion. Three of these dicyanamide anions coordinate the mercury ion with their terminal nitrogen atoms (d(Hg–N1) = 2.166(10), d(Hg–N3) = 2.612(12), and d(Hg–N3) = 2.834(10) Å), whilst the others coordinate via their bridging nitrogen at a more distant d(Hg–N2) = 3.084(9) and 3.412(22) Å. Similar distorted coordination octahedra are also known for Hg2Cl2 [26] (Figure 2).
Tl[dca] crystallizes isotypically to α-K[dca] and α-Rb[dca] [7] in the orthorhombic space group Pbcm (no. 57) with a = 8.5770(17), b = 6.4756(13), c = 7.2306(14) Å, and Z = 4. This is not surprising due to the similar ionic radii of all three cations, Tl+, K+, and Rb+. The structure is built of layers of Tl+ and [dca]−, in which Tl+ is coordinated by six terminal nitrogen atoms with d(Tl–N1) = 3.082(4)/3.089(4) and d(Tl–N3) = 2.870(4) Å and two bridging nitrogen atoms with d(Tl–N2) = 3.053(5) Å of eight different [dca] moieties, generating a distorted square antiprism (Figure 3). These Tl–N distances are in good agreement with those that were reported for a quadratic antiprismatic coordination polyhedron in TlN3 [27] with d(Tl–N) = 3.03 Å.
Like before, the boomerang-shaped dicyanamide in Tl[dca] exhibits atomic distances and angles in the expected range: the bond length of d(C1–N1) = 1.148(8) and d(C2–N3) = 1.148(7) Å of the terminal C–N pairs indicate triple bonds, while the central C–N with d(C1–N2) = 1.316(8) and d(C2–N2) = 1.319(7) Å of the [dca] anion are also typically found for such a moiety, with ∡(N1–C1–N2) = 172.0(6)°, ∡(N2–C2–N3) = 172.6(6)°, and ∡(C1–N2–C2) = 120.6(6)° (Table 1).
Given the large number of structurally characterized dicyanamides, it is tempting to finally investigate their volume chemistry. Hence, we calculated the volume increment of the dicyanamide anion according to the method of Biltz, that is, taking into account the tabulated volume increments [28] of the monovalent cations M+, namely those of Li, Na, K, Rb, Cs, Cu, Ag, Hg, Tl, and NH4. As shown in Table 2, the dicyanamide anion has a volume of 44.3(17) cm3·mol−1 on average, so it is about 70% larger than the NCN2− cyanamide anion (26 cm3·mol−1) [29] That being said, the dicyanamide anion appears as a mid-heavy (66.04 u) but relatively spacious pseudohalide, and it finalizes the trend found [28] for the true halides (F−: 9.5, Cl−: 20, Br−: 25, I−: 34, [dca]−: 44 cm3·mol−1). For completeness, we add that the calculated [dca]− volume increments for Hg2[dca]2 and Tl[dca] (40.2 and 41.9 cm3·mol−1) appear as slightly smaller, which is probably due to the fact that these crystal structures were determined at a lower temperature (Table 2).
2.2. IR-Spectra
3. Materials and Methods
3.1. Syntheses
Crystalline powder of Hg2[dca]2 was synthesized by mixing stoichiometric amounts of Na[dca] and Hg2(NO3)2·2H2O in water, followed by precipitation, but the fine powder was unsuitable for single-crystal diffraction. Better crystals of Hg2[dca]2 were subsequently obtained by a diffusion reaction. An aqueous solution of Hg2(NO3)2·2H2O (5 mL, c = 0.05 M) was layered below, and another aqueous solution of Na[dca] (5 mL, c = 0.1 M) was layered above an aqueous solution of NaNO3 (5 mL, c = 0.22 M) in a regular test-tube. Colorless, transparent crystals of Hg2[dca]2 grew within two days in the region between the layers of Hg2(NO3)2 and NaNO3.
Tl[dca] was obtained by adding TlBr (184.8 mg, 0.65 mmol) to an aqueous Ag[dca] (120.5 mg, 0.69 mmol, 5 mL deionized H2O) suspension. The synthesis of Ag[dca] has been described in a previous paper [23]. The suspension was stirred for twelve hours under the exclusion of light. 1 mL of the silver bromide-free solution was taken, and the water was evaporated in a desiccator. A colorless, transparent, orthorhombic crystal of Tl[dca] suitable for single-crystal X-ray diffraction was selected for diffraction data collection.
3.2. Single Crystal Diffraction
A suitable single crystal of Hg2[dca]2 was mounted on a glass fiber. Intensity data were collected with a STOE STADIVARI Dectris Pilatus 200K detector (STOE & Cie GmbH, Darmstadt, Germany), equipped with a GeniX Mo High Flux source (Mo Kα radiation, λ = 0.71073 Å, multilayer optics). Temperature control was achieved using an Oxford Cryostream 800 (Oxford Cryosystems Ltd., Oxford, UK) at 100 K. Collected data were integrated with X-Area Integrate [30], and Gaussian-integration absorption corrections were applied with STOE X-Red [31]. The structure was solved by charge-flipping methods (Superflip [32]) and refined on F2, as implemented in Jana2006 [33]. More crystallographic details can be found in Table 4, Table 5 and Table 6. The goodness-of-fit is unusually large (3.60) and it probably goes back to the rather high absorption coefficient for Mo Kα radiation resulting in an imperfect absorption model.
A suitable single crystal of Tl[dca] was adhered to a 100 µm MiTeGen loop using perfluoropolyether PFO-XR75. Intensity data were collected on a FR 591 rotating anode that was equipped with an Incoatec Helios focusing multilayer optic (Mo Kα radiation, λ = 0.71073 Å) and a Bruker AXS Enraf-Nonius KappaCCD detector (Bruker AXS GmbH, Karlsruhe, Germany). The temperature of the crystal was maintained at 100 K using an Oxford Cryostream 700 (Oxford Cryosystems Ltd., Oxford, United Kingdom). Diffraction data were integrated with the program REVALCCD ver. 1.6, 2008 and a Gaussian integration absorption correction based on the crystal shape was applied using SADABS [34]. Data preparation and reciprocal space exploration were performed by XPREP [35]. The structure was solved with SHELXT [36] by a dual-space method and was refined on F2, as implemented in SHELXL [37]. Crystallographic details can be found in Table 4, Table 7 and Table 8.
Additional details concerning the structure determination are available in CIF format (see Supplementary Materials) and have been deposited under the CCDC entry numbers 1881933 for Tl[dca] and 1881934 for Hg2[dca]2. Copies of the data can be obtained free of charge from CCDC (http://www.ccdc.cam.ac.uk/conts/retrieving.html).
3.3. Infrared Spectra
The IR spectra were recorded using an ALPHA II FT-IR-spectrometer (Bruker Optik GmbH, Ettlingen, Germany), equipped with an ATR Platinum Diamond measuring cell. All measurements were undertaken within the range of 4000 to 400 cm−1.
4. Conclusions
The compounds Hg2[dca]2 and Tl[dca] were synthesized, their respective crystal structures were determined, and their IR spectra were measured. While the structure of Hg2[dca]2 shows similarities to the structure of Hg2Cl2, Tl[dca] is isostructural to α-K[dca] and α-Rb[dca]. The [dca]‒ pseudohalide exceeds I− in its volume increment. The acquired data of the IR spectra are similar to the data of the previously reported dicyanamides.
Supplementary Materials
The following are available online at https://www.mdpi.com/2304-6740/6/4/135/s1: CIF and CIFchecked files.
Author Contributions
M.M. and O.R. conceived and designed the experiment; M.M. performed the syntheses, ATR-IR experiments and the single-crystal X-ray diffraction (SXRD) of Hg2[dca]2; N.N. and R.G. performed the SXRD of Tl[dca]; results were discussed with all authors; M.M. wrote the paper in collaboration with all co-authors.
Funding
This research received no external funding.
Acknowledgments
Nils Nöthling and Richard Goddard would like to thank Martin Jäger and Joachim Horst, Labor für Instrumentelle und Umweltschutzanalytik, Hochschule Niederrhein, Krefeld, Germany, for helpful discussions.
Conflicts of Interest
The authors declare no conflict of interest.
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Figure 1.
Crystal structure of Hg2[dca]2. The atomic displacement ellipsoids correspond to 90% probability using the refined anisotropic displacement parameters (ADPs).
Figure 1.
Crystal structure of Hg2[dca]2. The atomic displacement ellipsoids correspond to 90% probability using the refined anisotropic displacement parameters (ADPs).
Figure 2.
Comparison of the crystal structures of Hg2[dca]2 and calomel, Hg2Cl2. (a) Coordination sphere of Hg in Hg2[dca]2. The atomic displacement ellipsoids correspond to 90% probability using the refined ADPs. (b) Crystal structure of Hg2Cl2 [26].
Figure 2.
Comparison of the crystal structures of Hg2[dca]2 and calomel, Hg2Cl2. (a) Coordination sphere of Hg in Hg2[dca]2. The atomic displacement ellipsoids correspond to 90% probability using the refined ADPs. (b) Crystal structure of Hg2Cl2 [26].
Figure 3.
Crystal structure of Tl[dca] with (a) showing the view along c and (b) along b. The atomic displacement ellipsoids correspond to 90% probability using the refined ADPs.
Figure 3.
Crystal structure of Tl[dca] with (a) showing the view along c and (b) along b. The atomic displacement ellipsoids correspond to 90% probability using the refined ADPs.
Figure 4.
Infrared spectra of Hg2[dca]2 (left) and Tl[dca] (right).
Table 1.
Selected angles (°) and bond lengths (Å) in Hg2[dca]2 and Tl[dca].
| Hg2[dca]2 | (°) | Tl[dca] | (°) |
|---|---|---|---|
| ∡(N1–C1–N2) | 171.6(14) | ∡(N1–C1–N2) | 172.0(6) |
| ∡(N2–C2–N3) | 173.2(13) | ∡(N2–C2–N3) | 172.6(6) |
| ∡(C1–N2–C2) | 119.4(10) | ∡(C1–N2–C2) | 120.6(5) |
| (Å) | (Å) | ||
| N1–C1 | 1.148(14) | N1–C1 | 1.148(8) |
| C1–N2 | 1.325(13) | C1–N2 | 1.316(8) |
| N2–C2 | 1.317(16) | N2–C2 | 1.319(7) |
| C2–N3 | 1.108(16) | C2–N3 | 1.148(7) |
| Hg–Hg | 2.518(3) | Tl–Tl (2×) | 3.6153(7) |
| Hg–N1 | 2.166(10) | Tl–Tl (2×) | 4.5129(7) |
| Hg–N2 | 3.412(11) | Tl–N1 (2×) | 3.089(4) |
| Hg–N2 | 3.084(9) | Tl–N1 (2×) | 3.082(4) |
| Hg–N3 | 2.612(12) | Tl–N2 (2×) | 3.053(5) |
| Hg–N3 | 2.834(10) | Tl–N3 (2×) | 2.870(4) |
Table 2.
Calculated molar volumes of [dca]− based on M[dca] crystal structures containing monovalent cations.
Table 2.
Calculated molar volumes of [dca]− based on M[dca] crystal structures containing monovalent cations.
| M[dca] | Cell Volume (Å3), Z | T (K) | Molar Volume (cm3·mol−1) | M+ Volume (cm3·mol−1) [28] | [dca]− Volume (cm3·mol−1) |
|---|---|---|---|---|---|
| NH4[dca] [4] | 428.32, 4 | 200 | 64.5 | 19.5 | 45.0 |
| Li[dca] [5] | 313.84, 4 | 170 | 47.2 | 1.5 | 45.7 |
| Na[dca] [8] | 345.25, 4 | 293 | 52.0 | 6.5 | 45.5 |
| α-K[dca] [7] | 390.31, 4 | 293 | 58.7 | 16 | 42.7 |
| β-K[dca] [7] | 416.78, 4 | 293 | 62.7 | 16 | 46.7 |
| γ-K[dca] [7] | 415.56, 4 | 293 | 62.5 | 16 | 46.5 |
| α-Rb[dca] [7] | 433.4, 4 | 293 | 65.2 | 20 | 45.2 |
| β-Rb[dca] [7] | 1778.31, 16 | 293 | 66.9 | 20 | 46.9 |
| Cs[dca] [6] | 919.74, 8 | 299 | 69.2 | 26 | 43.2 |
| Cu[dca] [12] | 332.21, 4 | 248 | 50.0 | 5 | 45.0 |
| Ag[dca], o [14] | 349.24, 4 | 293 | 52.6 | 9 | 43.6 |
| Ag[dca], tr [14] | 256.36, 3 | 293 | 51.4 | 9 | 42.4 |
| Hg2[dca]2 | 186.84, 1 | 100 | 112.4 | 16 | 40.2 |
| Tl[dca] | 401.60, 4 | 100 | 60.4 | 18.5 | 41.9 |
Table 3.
IR data of Hg2[dca]2 and Tl[dca]. All numbers are given in cm−1.
| Vibration | ν(Hg2[dca]2) | ν(Tl[dca]) |
|---|---|---|
| σas(N–C≡N) | 493/515 | 517 |
| σs(N–C≡N) | 662 | 656 |
| νs(N–C) | 934 | 905 |
| νas(N–C) | 1354 | 1323 |
| νas(N≡C) | 2171 | 2119 |
| νas(N–C) + νs(N–C) | 2243 | 2191 |
| νs(N≡C) | 2301 | 2247 |
| νas(N≡C) + νs(N–C) | 3072 | 3010/2972 |
| νs(N≡C) + νas(N–C) | 3577 | 3508 |
Table 4.
Summary of single-crystal X-ray diffraction structure determination data of Tl[dca] and Hg2[dca]2.
Table 4.
Summary of single-crystal X-ray diffraction structure determination data of Tl[dca] and Hg2[dca]2.
| Chemical Formula | Hg2[dca]2 | Tl[dca] |
|---|---|---|
| Formula weight (g∙mol−1) | 533.3 | 270.42 |
| Crystal system | triclinic | orthorhombic |
| Space group | P (no. 2) | Pbcm (no. 57) |
| Temperature (K) | 100(2) | 100(2) |
| a (Å) | 3.7089(5) | 8.5770(17) |
| b (Å) | 6.4098(6) | 6.4756(13) |
| c (Å) | 8.150(6) | 7.2306(14) |
| α (°) | 81.575(6) | 90 |
| β (°) | 80.379(7) | 90 |
| γ (°) | 80.195(7) | 90 |
| V (Å3) | 186.84(14) | 401.60(14) |
| Z | 1 | 4 |
| Radiation, λ (Å) | Mo Kα, 0.71073 | Mo Kα, 0.71073 |
| μ (mm−1) | 41.09 | 40.022 |
| Crystal shape and color | Colorless block | Colorless block |
| Crystal size (mm3) | 0.17 × 0.08 × 0.02 | 0.05 × 0.04 × 0.02 |
| ρcalcd (g∙cm−3) | 4.739 | 4.473 |
| Diffractometer | STOE STADIVARI with Hybrid Pixel Counting Detector | Bruker AXS Enraf-Nonius with KappaCCD Detector |
| Absorption correction | Gaussian Integration, STOE X-RED | Gaussian Integration, SADABS 2014/15 |
| Tmin, Tmax | 0.0672, 0.6730 | 0.15236, 0.46282 |
| No. of measured, independent and observed [I > 3σ(I)] reflections | 3671 | 8880 |
| 1263 | 816 | |
| 1154 | 549 | |
| Robs | 4.68 | 1.87 |
| wR2obs | 10.88 | 3.94 |
| Rall | 4.92 | 3.25 |
| wR2all | 10.91 | 4.46 |
| GOFobs | 3.60 | 1.09 |
| No. of parameters, restraints | 55, 0 | 36, 0 |
Table 5.
Atomic coordinates (all on 2i) and equivalent isotropic displacement parameters Ueq (Å2) of Hg2[dca]2.
Table 5.
Atomic coordinates (all on 2i) and equivalent isotropic displacement parameters Ueq (Å2) of Hg2[dca]2.
| Atom | x | y | z | Ueq |
|---|---|---|---|---|
| Hg | 0.96205(10) | 0.90300(6) | 0.14632(4) | 0.01463(12) |
| N1 | 0.923(3) | 0.805(2) | 0.4137(12) | 0.024(3) |
| N2 | 0.619(3) | 0.7427(15) | 0.7062(10) | 0.015(2) |
| N3 | 0.406(3) | 0.4138(17) | 0.8391(12) | 0.020(3) |
| C1 | 0.765(3) | 0.7693(19) | 0.5460(13) | 0.016(3) |
| C2 | 0.510(3) | 0.559(2) | 0.7710(14) | 0.018(3) |
Table 6.
Anisotropic displacement parameters Uij (Å2) of Hg2[dca]2.
| Atom | U11 | U22 | U33 | U23 | U13 | U12 |
|---|---|---|---|---|---|---|
| Hg | 0.01303(19) | 0.0173(2) | 0.01206(19) | −0.00301(13) | 0.00010(12) | 0.00189(13) |
| N1 | 0.026(5) | 0.038(6) | 0.011(4) | −0.014(4) | 0.005(3) | −0.012(4) |
| N2 | 0.023(4) | 0.012(4) | 0.009(3) | 0.001(3) | −0.001(3) | −0.004(3) |
| N3 | 0.025(5) | 0.018(5) | 0.018(4) | −0.005(4) | −0.002(3) | −0.006(3) |
| C1 | 0.008(4) | 0.022(5) | 0.018(4) | −0.005(4) | 0.000(3) | 0.000(4) |
| C2 | 0.006(4) | 0.027(6) | 0.020(5) | −0.002(4) | 0.004(3) | −0.010(4) |
Table 7.
Atomic coordinates and equivalent isotropic displacement parameters Ueq (Å2) of Tl[dca].
| Atom | Site | x | y | z | Ueq |
|---|---|---|---|---|---|
| Tl | 4c | 0.31674(2) | ¼ | ½ | 0.01287(6) |
| N1 | 4d | 0.5898(6) | 0.3835(8) | ¾ | 0.0183(10) |
| N2 | 4d | 0.7848(7) | 0.1054(9) | ¾ | 0.0218(12) |
| N3 | 4d | 0.0707(6) | 0.1391(8) | ¾ | 0.0194(10) |
| C1 | 4d | 0.6880(5) | 0.2630(11) | ¾ | 0.0144(10) |
| C2 | 4d | 0.9369(7) | 0.1356(9) | ¾ | 0.0150(10) |
Table 8.
Anisotropic displacement parameters Uij (Å2) of Tl[dca].
| Atom | U11 | U22 | U33 | U23 | U13 | U12 |
|---|---|---|---|---|---|---|
| Tl | 0.01236(9) | 0.01241(10) | 0.01384(9) | −0.00016(13) | 0 | 0 |
| N1 | 0.0111(19) | 0.013(2) | 0.031(3) | 0 | 0 | −0.002(2) |
| N2 | 0.012(2) | 0.010(2) | 0.043(4) | 0 | 0 | −0.003(2) |
| N3 | 0.015(2) | 0.012(2) | 0.031(3) | 0 | 0 | 0.0007(19) |
| C1 | 0.012(2) | 0.009(3) | 0.022(3) | 0 | 0 | −0.003(3) |
| C2 | 0.017(3) | 0.008(2) | 0.020(3) | 0 | 0 | −0.002(2) |
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Mann, M.; Reckeweg, O.; Nöthling, N.; Goddard, R.; Dronskowski, R. Syntheses and Characterization of Two Dicyanamide Compounds Containing Monovalent Cations: Hg2[N(CN)2]2 and Tl[N(CN)2]. Inorganics 2018, 6, 135. https://doi.org/10.3390/inorganics6040135
AMA Style
Mann M, Reckeweg O, Nöthling N, Goddard R, Dronskowski R. Syntheses and Characterization of Two Dicyanamide Compounds Containing Monovalent Cations: Hg2[N(CN)2]2 and Tl[N(CN)2]. Inorganics. 2018; 6(4):135. https://doi.org/10.3390/inorganics6040135
Chicago/Turabian StyleMann, Markus, Olaf Reckeweg, Nils Nöthling, Richard Goddard, and Richard Dronskowski. 2018. "Syntheses and Characterization of Two Dicyanamide Compounds Containing Monovalent Cations: Hg2[N(CN)2]2 and Tl[N(CN)2]" Inorganics 6, no. 4: 135. https://doi.org/10.3390/inorganics6040135
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