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"The first study uses tunable vacuum-ultraviolet radiation from a synchrotron to identify negative ions from twenty four photoexcited polyatomic molecules in the gas phase. From these experiments, Matthew collects a vast amount of data and summarises and reviews ion-pair formation from polyatomic molecules. The second study is on selected ion flow tube mass spectrometry. Matthew investigates the reactions of cations and anions with ethene, monofluoroethene, 1,1-difluoroethene and tetrafluoroethene. In this study Matthew tries to explain why certain products are formed preferentially over other products at a microscopic level of understanding. "

"Fenomena localized surface plasmon resonance (LSPR) pada nanowire memiliki dua mode eksitasi berbeda yang sangat bergantung pada polarisasi gelombang eksitasinya, yaitu mode polarisasi longitudinal (mode transverse electric) dan mode polarisasi transversal (mode transverse magnetic). Kedua mode eksitasi masing – masing memiliki karakteristik yang unik. Mode transverse electric memiliki pola spektra LSPR dengan beberapa puncak resonansi yang terpisah jelas dan dapat dibedakan, sedangkan mode transverse magnetic hanya memiliki puncak resonansi tunggal pada frekuensi tinggi. Pada penelitian ini, akan dilakukan pemodelan spektra LSPR nanowire perak dengan beberapa variasi bentuk dan ukuran. Fungsi dielektrik perak diperoleh dari penelitian Johnson dan Christy (1972). Ada dua jenis nanowire yang dimodelkan: nanowire dengan tutup ujung rata (flat) dan tutup ujung setengah bola (hemi-spherical). Untuk mengetahui pengaruh perubahan bentuk dan ukuran nanopartikel, pemodelan yang dilakukan menggunakan nanowire dengan diameter 10, 30, dan 50 nanometer serta aspect ratio sebesar 10, 12, 14, 16, 18, dan 20. Hasil pemodelan mode TE menunjukkan spektra LSPR dengan beberapa puncak resonansi yang terpisah jelas. Banyaknya puncak resonansi ini diduga berasal dari adanya interferensi konstruktif gelombang berdiri surface plasmon polariton (SPP) pada nanowire. Berbeda dengan prediksi awal, hasil pemodelan mode TM menunjukkan dua buah puncak resonansi. Kedua puncak resonansi ini dapat dikaitkan dengan osilasi plasmon mode transversal dan longitudinal pada nanowire.

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The localized surface plasmon resonance (LSPR) phenomenon on nanowires possess two distinct excitation modes that depend on the polarization of the exciting planewave, the longitudinal polarization mode (transverse electric mode) and the transversal polarization mode (transverse magnetic mode). Both excitation modes exhibit unique optical spectra characteristics. The optical spectra of the transverse electric mode exhibit multiple, wellseparated resonance peaks while the optical spectra of the transverse magnetic mode only exhibit a single resonance peak spectrally located at a high frequency. In this study, we have simulated the optical LSPR spectra of silver nanowires with several size variations. The dielectric function of silver was obtained through Johnson and Christy’s previous work (1972). Two nanowire types with different end-cap shapes on each end were simulated: one having a flat end-cap shape and the other having a hemi-spherical end-cap shape. In order to discover the effects of nanoparticle size change, the simulation was done on nanowires with diameters 10, 30, and 50 nanometers along with aspect ratios of 10, 12, 14, 16, 18, and 20. The TE mode simulations result in an optical spectrum exhibiting multiple, well-separated resonance peaks. These multiple peaks are assumed to arise from the constructive interference of surface plasmon polaritons (SPPs) excited on the surface of the nanowire. Unlike previous observations, the TM mode simulations result in an optical spectrum which exhibit two resonance peaks. Both peaks can be attributed to the transversal and longitudinal plasmon oscillations which occur on the nanowire."

"This handbook is a breakthrough in the understanding of the large number of spectral lines in diamond. Data on more than 2000 lines and bands are presented in 200 tables, including many unpublished results. In order to meet the interest in the understanding of the spectra, structure assignments for 80 % of the lines are given, of which 15 % only were published before. The majority of the structures for the 300 centers is explained in most cases for the first time."