Magnonics concepts utilize spin-wave quanta (magnons) for information transmission, processing and storage. To convert information carried by magnons into an electric signal promises compatibility of magnonic devices with conventional electronic devices, that is, magnon spintronics . Magnons in inorganic materials have been studied widely with respect to their generation, transport and detection . In contrast, resonant spin waves in the room-temperature organic-based ferrimagnet vanadium tetracyanoethylene (V(TCNE) (x ≈ 2)), were detected only recently . Herein we report room-temperature coherent magnon generation, transport and detection in films and devices based on V(TCNE) using three different techniques, which include broadband ferromagnetic resonance (FMR), Brillouin light scattering (BLS) and spin pumping into a Pt adjacent layer. V(TCNE) can be grown as neat films on a large variety of substrates, and it exhibits extremely low Gilbert damping comparable to that in yttrium iron garnet. Our studies establish an alternative use for organic-based magnets, which, because of their synthetic versatility, may substantially enrich the field of magnon spintronics.

The energy levels for free and for hindered pseudorotation have been obtained by matrix diagonalisation. The problem has been solved both by factorisation of the Hamiltonian and without this approximation. Differences arise between the two sets of results, which indicates that pseudorotational parameters obtained from a factored Hamiltonian may have systematic errors. The calculated energy levels have been applied to cyclopentane, tetrahydrofuran and 1,3-dioxolan. 1 FIG. 3.-Variation of the pseudorotational intervals with I for several values of u, marked on curves,

Li[TCNE] (TCNE = tetracyanoethylene) magnetically orders as a weak ferromagnet (canted antiferromagnet) below 21.0 ± 0.1 K, as observed from the bifurcation of the field-cooled and zero-field-cooled magnetizations, as well as remnant magnetization. The structure, determined ab initio from synchrotron X-ray powder diffraction data, consists of a planar μ4-[TCNE](•-) bound to four tetrahedral Li(+) ions. The structure consists of two interpenetrating diamondoid sublattices, with closest interlattice distances of 3.43 and 3.48 Å. At 5 K this magnetic state is characterized by a coercivity of ~30 Oe, a remnant magnetization of 10 emu·Oe/mol, and a canting angle of 0.5°.

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Basic principles of Redfield's 1927 enumeration theory are reviewed. The theory is shown to incorporate, supersede, and simplify many of the last decade's developments in molecular combinatorics.

Organic semiconductors find increasing importance in spin transport devices due to the modulation and control of their properties through chemical synthetic versatility. The organic materials are used as interlayers between two ferromagnet (FM) electrodes in organic spin valves (OSV), as well as for magnetic spin manipulation of metal-organic complexes at the molecular level. In the latter, specifically, the substrate-induced magnetic switching in a paramagnetic molecule has been evoked extensively, but studied by delicate surface spectroscopies. Here we present evidence of the substantial magnetic switching in a nanosized thin film of the paramagnetic molecule, tris(8-hydroxyquinoline)iron(III) (Feq3) deposited on a FM substrate, using the magnetoresistance response of electrical 'spin-injection' in an OSV structure; and the inverse-spin-Hall effect induced by state-of-art pulsed microwave 'spin-pumping'. We show that interfacial spin control at the molecular level may lead to a macroscopic organic spin transport device; thus, bridging the gap between organic spintronics and molecular spintronics.

Hexacyanobutadiene (HCBD) and M(CO)x (M = V, x = 6; Fe, x = 5) react in CH2Cl2 to form new organic-based magnets of M[HCBD]2·z(CH2Cl2) composition. Analysis of the IR spectrum [M = V: ν(CN) 2193 and 2116 cm(-1) (fwhh ∼400 cm(-1)); Fe: 2196 and 2145 (fwhh ∼150 cm(-1))] suggests that HCBD is reduced to the radical anion, [HCBD](•-), and the broadness suggests multiple and variable nitriles sites are coordinated to the V(II), leading to a complex mixture of magnetic couplings and behaviors that deviate from paramagnetic behavior below ∼150 K, and a frustrated magnet with Tc ≈ 9 K is observed for V[HCBD]2, the first cyanocarbon-based frustrated magnet. Fe[HCBD]2 behaves as a weak ferromagnet (canted antiferromagnet) with some spin glass behavior with a 10 K Tc.

The pressure dependence of the magnetic properties of rhombohedral Na2Mn­[Mn­(CN)6] up to 10 kbar has been studied. The magnetic ordering temperature, T c, for Na2Mn­[Mn­(CN)6] reversibly increases with increasing applied hydrostatic pressure, P, by 9.0 K (15.2%) to 68 K at 10 kbar with an average rate of increase, dT c/dP, of 0.86 K/kbar. The magnetization at 50 kOe and remanent magnetization, M r(H), remain constant with an average value of 13,100 ± 200 and 8500 ± 200 emuOe/mol. The coercive field H cr increases by 12% from 13,400 to 15,000 Oe. The increase and rate of increase of T c for rhombohedral Na2Mn­[Mn­(CN)6] are reduced with respect to monoclinic A2Mn­[Mn­(CN)6] (A = K and Rb), but they are still greater than those of cubic Cs2Mn­[Mn­(CN)6]. This is attributed to the compression of the MnNC framework bonding without decreasing ∠MnIINC, maintaining the unit cell in accord with cubic A = Cs at lower applied pressures, and not due to reduction in ∠MnIINC, which correlates with increasing T c that is reported for A = K and Rb as well as Cs at higher applied pressures.