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2. Mass Spectrometry and Gas-Phase Ion Chemistry

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2. Mass Spectrometry and Gas-Phase Ion Chemistry Universidade de Lisboa Faculdade de Ciências (Departamento de Química e Bioquímica) EXPLORING THE CHEMICAL PROPERTIES OF ELEMENTARY ACTINIDE SPECIES IN THE GAS PHASE Ana Filipa Folgado de Lucena Tese orientada por Doutor Joaquim Marçalo (C2TN-IST), Doutor John K. Gibson (LBNL) e Doutor João Paulo Leal (FCUL, C2TN-IST), Documento especialmente elaborado para a obtenção do grau de Doutor em Química, especialidade Química-Física 2015 The work presented in this thesis was performed at Grupo de Química dos Elementos-f, Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa (C2TN/IST), and also at Glenn T. Seaborg Center, Chemical Sciences Division, Lawrence Berkeley National Laboratory (LBNL) and Laboratory of Ligand-Actinide Interactions (LILA) at Comissariat à l’Energie Atomique et aux Energies Alternatives (CEA), with financial support from the Fundação para a Ciência e a Tecnologia (SFRH/BD/70475/2010). To my husband and my daughter To my mother Acknowledgments There are a great number of people that have contributed, directly or indirectly, to the completion of this thesis and without whom this journey would be much harder, if not, impossible. First of all, I would like to express my sincere gratitude to my thesis supervisors: Dr. Joaquim Marçalo, who generously suggested and invited me to go through this Ph.D., and has always motivated and supported me with his knowledge and competence. Although he is a very busy researcher, he always arranged time to explain and to make me aware of several important aspects, with a remarkable memory, sometimes better than mine! Thank you for leading me into the world of the gas-phase ion chemistry and to continuously challenging me, making me progress and grow as a scientist. Dr. John K. Gibson, for hosting me at the Lawrence Berkeley National Laboratory with enormous sympathy, for his supervision with the actinides experiments, for all the scientific discussions together with Dr. Joaquim Marçalo, and the prompt corrections and email answers. Dr. João Paulo Leal for accepting to supervise my work and being always available for any corrections and suggestions, and for being the link with the University, helping me with all the bureaucratic issues. I would also like to acknowledge the Foundation for Science and Technology (FCT) for my personal doctoral grant (SFRH/BD/70475/2010) and to Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa (C2TN/IST) for hosting and providing me the necessary conditions to develop my work. A special thanks to all the co-authors of the works described in this thesis. It would have never been possible to accomplish the reported results and conclusions if it wasn’t your important contribution. A special thanks to Dr. Maria Michelini for the theoretical computations and for such kindness and sympathy during my stay in Berkeley. To Dr. Yu Gong, for guiding me with all the actinide ESI-MS experiments at LBNL and through all the necessary procedures to work under a radiological environment, more specifically with the radiologic glove box. Also, thank you for the hints and tips about Berkeley and San Francisco, for showing me the criminal map of Oakland and for understanding that a left-handed woman doesn't bring bad luck! I want also to acknowledge the LILA Lab, at CEA France, specially Dr. Laurence Berthon and Mrs. Nicole Zorz for guiding me with the americium experiments. Also, I want to thank Mathieu Audras and Sarah Mostapha for the companionship at the office/lab and during my stay in France. I would like also to acknowledge Dr. M. Conceição Oliveira and Mrs. Ana Dias, for the collaboration and all the ESI-MS experiments performed at CQE-IST. To Grupo de Química dos Elementos-f at C2TN-IST, in particular to Dr. Leonor Maria, for the scientific discussions, for all the suggestions regarding my thesis and for motivating me during all these years; it was a pleasure to work with you. To Dr. José Carretas, who collaborated in most of the experiments of my work, showing up always in a good mood, always “moralizado”. To Adelaide Cruz, for helping me at the lab and sharing the office with me during all these years, spreading laughs and happiness everywhere. To my co-workers and friends - “as meninas” Cybelle ix Soares, Marina Soares, Joana Vitorino, Vânia Sousa, Ana Ferreira and Ana Moura, thank you for sharing all the good and bad moments of this journey, for listening and advising me. A special thanks also to the former grantholders and my dearest friends Célia Lourenço and Elsa Mora, who were present since the very beginning of this journey. To Dr. Joaquim Branco, Dr. Teresa Gasche, Dr. Maria Augusta Antunes, Dr. Bernardo Monteiro and Dr. Cláudia Pereira, for the important comments and discussions at every group meeting. To all my QA friends from the Faculdade de Ciências e Tecnologia, who directly or indirectly made my days better, specially, Catarina Custódio (a minha Pucca), Vanessa Nascimento, Ricardo Barata, Sofia Martins, Raquel Teixeira, Joana Pais, Patrique Nunes, Cristina Oliveira, Bárbara Chagas, Ricardo Melo, António Barata, Leonardo Mendes, Vitor Silva, André Costa, most of you great scientists, thank you all for the friendship, the days spent at Dona Teresa and at the Sala de convívio playing endless sueca, the nights out, all the weird geek discussions, all the laughs and the support in every moment of my life, that greatly contributed for who I am today. To my new friends in Italy, le ragazze: Suzanne, Sylvia, Kaat, Manuela, Carolina, Vera, Heidi, Amelia, Nami and Mrs. Giuliana Potts (insegnante di italiano), per le ottime pause pranzo ogni martedì. È stato sicuramente il giorno più bello della settimana! Un bacione a tutti voi! I would like to acknowledge also the ones that have always supported me in the background: my family, aos Lopes e Mendes, queridas manas Inês e Andreia, fofinhos Margarida e Miguel e Avó Alice; à minha avózinha Lia, aos meus tios Sú, Cadi e Lívia e primos AlexDaTuga e Catas. À minha querida mãe, pelo seu amor incondicional e achar que eu sou “a maior”, e, por último, um agradecimento mais que especial ao meu melhor amigo, companheiro, marido e pai, João, e à nossa bebé Filipa, vocês são a base da pirâmide – obrigada por tudo. Por último, dedico a tese em memória do meu Pai, que sempre me incentivou a progredir e que ficaria certamente orgulhoso de me ver atingir tamanha conquista. x Exploring the chemical properties of elementary actinide species in the gas phase Abstract Gas-phase ion chemistry studies were conducted to search for new elementary actinide (An) species and reactions and to enhance the fundamental understanding of these elements. In the gas phase, with the absence of external perturbations (solvents), physical and chemical properties of elementary actinide species were better studied and relationships between electronic structure, reactivity and energetics established. The role of the 5f electrons and the covalency in these heavy elements were important aspects examined. Most of the studies were performed in parallel with theoretical calculations (through international collaborations), which were essential for complementing the understanding of actinide chemistry. The studies were performed with the use of mass spectrometry techniques, namely Laser Ionization Fourier Transform Ion Cyclotron Resonance (LI-FT-ICR-MS) and Electrospray Ionization Quadrupole Ion Trap (ESI-QIT-MS). The use of these ion traps were very effective for the ion/molecule reaction studies, enabling to perform complex sequences of ion manipulation and obtaining kinetic and mechanistic information. New +/2+ actinide species and processes were identified, with the actinyl ions, AnO2 , being the highlight of the work: oxo-exchange with water and methanol; addition reactions of water and oxygen to actinyl ions, with a focus in the formation of superoxide uranyl(VI) ions from uranyl(V); synthesis of sulfur “analogues” of actinyls from reactions of An+/2+ ions with COS; determination of the effective charge density of U in uranyl(VI), comparable to that of the late trivalent lanthanides, from the dissociation of bimetallic clusters; evaluation of III/IV redox stabilities of lanthanides and - actinides by measurement of hydrolysis rates for MO(NO3)3 species; and coordination studies of biologically relevant ligands, amino acids in particular, that allowed establishing trends of relative stabilities/affinities towards the actinyl ions. Keywords Gas-phase ion chemistry, FT-ICR-MS, ESI-QIT-MS, Actinyl ions, Ion/molecule reactions, Collision-induced dissociation, 5f electrons. xi xii Estudo das propriedades químicas de espécies elementares de actinídeos em fase gasosa Resumo Foram efetuados estudos de química de iões em fase gasosa com o objetivo de obter novas espécies e reações de actinídeos (An) e ampliar o conhecimento destes elementos a nível fundamental. Devido à ausência de fatores externos na fase gasosa, nomeadamente solventes, é possível realizar estudos mais precisos das propriedades físicas e químicas de espécies com actinídeos e estabelecer relações entre reatividade, energética e estrutura eletrónica. O papel dos eletrões 5f e a covalência neste tipo de elementos foram dois aspetos importantes abordados. A parte experimental foi realizada em simultâneo com cálculos teóricos, através de colaborações internacionais, que foram essenciais uma vez que permitiram complementar o conhecimento da química dos actinídeos. Recorreu-se ao uso de técnicas de espectrometria
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