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"This book about more than just distances from electron density studies, modeling and analysis of hydrogen atoms, charge density methods in hydrogen bond studies. some main group chemical perceptions in the light of experimental charge density investigations. electronic structure and chemical properties of lithium organics seen through the glasses of charge density. bond orders in metal–metal interactions through electron density analysis, and on the nature of β-agostic interactions : a comparison between the molecular orbital and charge density picture."

"This book about new directions in pseudoatom-based X-ray charge density analysis, reliable measurements of dipole moments from single-crystal diffraction data and assessment of an in-crystal enhancement, challenging problems in charge density determination : polar bonds and influence of the environment, electron density in quantum theory, residual density analysis, the source function descriptor as a tool to extract chemical information from theoretical and experimental electron densities."

"This book focuses on state-of-the-art methods and applications of electron-density analysis. It is a field traditionally associated with understanding chemical bonding and the electrostatic properties of matter. Recently, it has also been related to predictions of properties and responses of materials (having an organic, inorganic or hybrid nature as in modern materials and bio-science, and used for functional devices or biomaterials)."

"ABSTRAKPenelitian ini membahas mengenai studi kelayakan material ekuivalen jaringan spesifik pada rentang energi radiodiagnostik 80 kV hingga 130 kV , yang dikontruksi menggunakan campuran bahan organik berupa tepung beras dan lilin batik gondorukem, cecek, parafin . Dari hasil studi pendahuluan, didapatkan 4 jenis komposisi material ekuivalen, yaitu material ekuivalen jaringan adiposa, jaringan otot, jaringan otak dan organ hati. Masing-masing komposisi material ekuivalen jaringan kemudian akan melalui dua jenis metode uji, yaitu metode Dual Energy Computed Tomography DECT untuk mengetahui karakteristik sampel melalui besaran Hounsfield Unit HU, dan metode stoikiometri menggunakan Energy Dispersive Spectroscopy EDS untuk mengetahui karakteristik sampel melalui susunan jenis atom. Masing-masing data dari kedua metode kemudian akan diolah hingga mendapat nilai densitas elektron ?e dan nomor atom efektif Zeff . Hasil kalkulasi untuk metode uji DECT pada material ekuivalen jaringan adiposa, jaringan otot, jaringan otak dan organ hati menunjukan kesalahan literatur minimum sebesar 0,605 ; 0,732 ; 0,751 ; 0,670 untuk densitas elektron ?e dan 26,345 ; 26,417 ; 25,089 ; 24,617 untuk nomor atom efektif Zeff. Sedangkan untuk metode Stoikiometri, pengukuran dianggap tidak akurat karena atom hidrogen yang tidak dapat terdeteksi. Dari hasil tersebut, dapat disimpulkan bahwa tingkat akurasi metode DECT lebih baik dibandingkan metode stoikiometri, dengan hasil analisa dari keempat sampel menunjukan kesesuaian respon terhadap jaringan target, namun hanya pada jenis energi tinggi 130kV.

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ABSTRACTThis research discusses the feasibility study of tissue specific equivalent material in radiodiagnostic energy range 80 kV to 130 kV, that are made from organic mixtures rice flour and waxes for batik gondorukem, cecek, paraffin . From the preliminary study, we obtain four types of equivalent material compositions, which are equivalent to adipose, muscle, brain, and liver. Each of the compositions will be evaluated using two methods, which is Dual Energy Computed Tomography DECT method in order to discover characteristic through Hounsfield Unit HU scale, and Stoichiometry with Energy Dispersive Spectroscopy EDS in order to discover characteristic through atoms composition. The test result then processed into the quantity of electron density e and effective atomic number Zeff . From DECT method, calculation of adipose, muscle, brain, and liver equivalent materials shows minimum literature error 0,605 0,732 0,751 0,670 for electron density e and 26,345 26,417 25,089 24,617 for effective atomic number Zeff . While for the Stoichiometric method, the measurement is considered inaccurate because the hydrogen atom cannot be detected. From these results, it can be concluded that the DECT method has better accuracy compared to stoichiometry method, which the four samples have a similar response that represents tissue target, but only when exposed with high energy 130kV ."