The basicities of simple organic bases – aliphatic and aromatic amines, amidines, phosphazenes, as well as saturated and unsaturated nitrogen heterocycles – are examined in acetonitrile, dimethyl sulfoxide, tetrahydrofuran, water and the gas phase. The basicities (pKaH values) of conjugate acids of a large variety of bases in these media are presented and discussed. Equations employing easily usable structural descriptors have been derived for approximately converting basicities from acetonitrile to other solvents. Recommendations are given on their practical use and a number of pKaH values that are experimentally unavailable are estimated from these relationships. An important part of the minireview is a large compilation of pKaH and GB values of the compounds in solvents and the gas phase, respectively, as well as the revised basicity scale in acetonitrile, now containing more than 270 pKaH values.

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The structures of a series of beryllium containing complexes have been optimized at the B3LYP/6-31G(d) level and their (9)Be magnetic shielding values have been determined using B3LYP/6-311G+g(2d,p) and the gauge-including atomic orbital (GIAO) method. The calculated chemical shifts are in excellent agreement with experimental values. The performance of a variety of NMR methods (SGO, IGAIM, CSGT) were also examined but were found to be inferior to the GIAO method at the chosen level of theory employed. The theoretical method has been utilized to predict the beryllium chemical shifts of structurally characterized complexes for which no measured (9)Be NMR spectrum exists, and to investigate a literature complex with an unusual (9)Be NMR chemical shift. A new standard for beryllium NMR in nonaqueous solvents has been suggested.

In this work we explored the relationship between the structure and solvent effects on the basicity of a large selection of conjugated N‐heterocyclic nitrogen bases in different media: the polar aprotic solvent acetonitrile, the polar protic solvent water and the gas phase. Altogether, 58 previously unpublished basicity values in different media for 39 compounds are presented, including 30 experimentally determined pKa values in acetonitrile. We present the pKa and gas‐phase basicity values for quino[7,8‐h]quinoline, which is one of the most basic conjugated nitrogen heterocyclic compounds without basicity‐enhancing substituents. The trends in basicity are rationalized by comparing the basicity data of related compounds in different solvents, as well as by using isodesmic reactions. The gas‐phase basicity is predominantly determined by the ability of a molecule to disperse the excess positive charge over a large number of atoms. In solution the situation is less clear and smaller systems with localized charge often lead to higher basicities because of solvent effects. In particular, it was found that the fusion of an additional benzene ring does not always lead to an increase in basicity in solution: its effect can be either basicity‐increasing or ‐decreasing, depending on the ring size, number and position of nitrogen atoms and medium. A correlation between the measured pKa values in MeCN and in water suggests that these two different solvents exert a similar effect on the basicity of the studied heterocycles.

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Advances in nanotechnology have resulted in the introduction of magnetic fluid hyperthermia (MFH), a promising noninvasive therapeutic localized cancer treatment. Exposure of a fluid of superparamagnetic iron oxide nanoparticles (IONPs) to an alternating magnetic field (AMF) operating at biologically benign conditions leads to heat dissipation within the tumor and ultimate apoptosis and/or necrosis. Despite use in a clinical setting, there are still impediments preventing widespread use of MFH. These include insufficient heat dissipation potency of IONP fluid, inadequate dose or concentration of deposited fluid to the tumor, inhomogeneous distribution of fluid inside the tumor, the lack of control of real‐time monitoring of temperature rises during treatment, and exposure of the patients to X‐ray radiation produced by computed tomography (CT) scans. Accordingly, massive efforts have been put forth to promote the successful clinical adoption of MFH. In this contribution, the technique of MFH is described, including the present state of clinical MFH. The physical mechanisms behind heat dissipation by magnetic nanoparticles (MNPs) that instigate cell death pathways are discussed, as is recent technological progress in the field toward the advancement of MFH. Finally, an outlook on the future considerations required to accelerate the clinical adoption of MFH is presented.

A spin crossover transition (350 K, μ =3.15 μ per Co atom; 4.5 K, μ =0.70 μ per Co atom) and weak antiferromagnetic exchange (2 J=-11.7 cm ) between the octahedral, doubly pyridazine bridged cobalt(II) ions are features of the structurally characterized complex [Co L(NCS) (SCN) ] (the ligand L is shown).

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