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This work involves the characterisation of reaction products of transition metals from the 1st, 2nd and 3rd rows of the Periodic Table with guanidines and their lithiated derivatives. Physical methods such as infrared spectroscopy, (^1)H, (^13)C and (^19)F nuclear magnetic resonance spectroscopy, microanalysis, and conductivity measurements have been used to characterise the materials. The transition metal compounds used in this work can be divided into two groups: (i) metal carbonyls and (ii) metal halides. The metal carbonyls group consists of [M(CO)(_5)L] (M = Mn, L = Br; M = Cr, Mo, W, L = CO), [Mo(Cl)L(CO)(_3)] (L = Ƞ-C(_5)H(_5)) and [MoL(CO)(_3)][BF(_4)] (L = Ƞ-C(_7)H(_7) ), and the metal halide group consists of MCl(_2) (M = Pd, Pt), MLCl(_2) (M = Pd and L = C(_8)H(_12)), K(_2)MCl(_4) (M = Pd, Pt) and WCl(_4). Studies have involved two substituted guanidines, 1,2,3-triphenylguanidine and syn-1,2- diphenylguanidine and the Uthiated derivative of 1,2,3-triphenylguanidine.The reactions were undertaken using a variety of conditions. The type of solvent, temperature and molar ratio are important parameters, particularly for the complexes of manganese. Similar conditions were explored for the complexes of palladium, platinum, chromium, molybdenum, tungsten and arylmolybdenum derivatives. Carbonyl complexes of the type [Mn(Br)(CO)(_3)L(_2)] (L = 1,2,3- triphenylguanidine), [Mn(Br)(CO)(_4)L] (L = 1,2,3-triphenylguanidine), [Mo(Ƞ-C(_5)H(_5))L(CO)(_2)] (L = 1,2,3-triphenylguanidino) and complexes of the type [M2CI4L2] (M = Pd, Pt; L = 1,2,3-triphenylguanidine, 1,2-diphenylguanidine), [Pt(_2)Cl(_4)L(_3)] (L = syn-1,2-diphenylguanidine), [Pt(_2)Cl(_4)L(_2)L'] (L = syn-1,2-diphenylguanidine, L' = N,N'-diphenylurea), [Pt(_2)Cl(_2)L(_2)L'(_2)] (L = syn-l,2-diphenylguanidino, L(^1) = syn-l,2- diphenylguanidine ), [PtCl(_2)L] (L = HNC(Me)NHC(Me)NH) and [PdCl(_2)(C(_8)H(_12))L] (L = 1,2,3-triphenylguanidine, syn-1,2-diphenylguanidine), were isolated. A product containing BF(_3) was isolated, and the bonding of the BF(_3) studied. The guanidine ligand adopts various bonding modes towards transition metals, and studies have been directed towards determining the mode adopted in each of the new complexes synthesised. Guanidines are found to act as strong o- bonding ligands, having consequences on the remaining ligands. Comparison is made throughout with the related amidine ligands. Mechanisms of reactions, consistent with experimental data, are discussed throughout the thesis.

Over the last 20 years increasing concentration of platinum metals in the environment was recorded. These hazardous metals come through anthropogenic activities in the aquatic and terrestrial ecosystem. It is therefore necessary to deal with their possible negative impact on organisms. This thesis is focused on the ecotoxicological evaluation of selected complex compounds of platinum metals, namely platinum and palladium. For ecotoxicity evaluation tests on following aquatic organisms were used: Daphnia manga, Thamnocephalus platyurus and Lemna minor. On the base of obtained results ecotoxicological values of LC50 and EC50 were calculated.

Made available in DSpace on 2014-10-09T12:49:39Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:11Z (GMT). No. of bitstreams: 1 09987.pdf: 6803672 bytes, checksum: c070bf0956c20ddeb4d6cb89d8d1535c (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:00/02118-9

Made available in DSpace on 2014-10-09T12:49:39Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:11Z (GMT). No. of bitstreams: 1 09987.pdf: 6803672 bytes, checksum: c070bf0956c20ddeb4d6cb89d8d1535c (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:00/02118-9

Made available in DSpace on 2014-10-09T12:26:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:18Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:26:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:18Z (GMT). No. of bitstreams: 0 / A avaliação dos sistemas de fornecimento de energia para o futuro é da maior importância para se obter informações sobre o potencial de impacto ambiental dos vários estágios do ciclo de vida das tecnologias inovadoras, determinando as vantagens competitivas sobre as tecnologias convencionais e para o desenvolvimento de cenários futuros. Este trabalho apresenta e caracteriza os tipos de pilhas combustíveis de média e baixa temperatura mais pesquisadas e comercializadas nos últimos anos. Realiza-se também a apresentação da avaliação do impacto ambiental dos principais materiais utilizados nas pilhas a combustível, considerando as fases de fabricação, operação e disposição final após o término da vida útil. São apresentados vários dados de LCA (Life Cycle Assessment) efetuados para alguns tipos de pilhas. O trabalho efetuou uma contribuição ao estudo da avaliação de impacto ambiental das pilhas a combustível de média e baixa temperatura utilizando a metodologia Delphi. Foi construído um questionário e um banco de dados para formação do conjunto de respondentes que participaram da pesquisa. Eles receberam o questionário na primeira rodada e o responderam. Depois receberam novamente o questionário em conjunto com as respostas obtidas na primeira etapa, para nova rodada de respostas. Ao final o estudo verifica se ocorreu aumento de consenso e a influência dos respondentes mais qualificados sobre os menos qualificados. Os resultados mostraram que os respondentes acreditam numa redução do impacto ambiental das pilhas. O mais surpreendente é que os respondentes acreditam que os catalisadores do grupo PGM Podem ser substituídos. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

This thesis was inspired by the discovery of Bi14Rh3I9, the first so-called weak three-dimensional topological insulator (3D-TI) and has been concerned with the topic of TIs in general. Two aspects were tackled to gain a deeper understanding of this new state of matter. On one hand, the expansion of the material’s basis and on the other hand developing a simple model of the structure and analysing it via density-functional theory (DFT) based methods. To discover new materials, a systematic investigation of the metal-rich parts of the bismuth–platinum-metal–iodine phase systems was conducted. It led to six new phases among the bismuth subiodides. Some of which, e.g. Bi14Rh3I9, share a honeycomb network of platinum-metal-centred bismuth-cubes and are the seed of a family of materials with this structural motive. The others show strand-like structures or layered structures with platinum-platinum bonds. The latter were so far unknown amongst bismuth subiodides. The honeycomb network was separately analysed and shown to host the TI properties. Structurally and electronically it can be seen as a “heavy graphene analogue”, which refers to the fact that graphene with hypothetical strong spin-orbit coupling (“heavy graphene”) was the first TI put forward by theoreticians. Apart from DFT-calculations, physical experiments confirmed the TI properties. Angle-resolved photoelectron spectroscopy (ARPES) was used to verify the electronic structure and scanning tunnelling microscopy and spectroscopy (STM and STS) to reveal the protected 1D edge states present at the cleaving surface of this material. As the arrangement of the honeycomb layer varies between the different known and newly discovered materials within this family of structures, this influence was also investigated. All further materials were also characterised by DFT-calculations and physical experiments, e.g. magnetisation and transport measurements. This thesis might give an experimental and theoretical basis for a deeper understanding of the TI state of matter. The 1D edge states on the surface of Bi14Rh3I9 could be a chance to handle spins and therefore propel spintronic research, or they could host Majorana fermions, which could be used as qubits in quantum computing.