The purpose of this research are to know about how Hydrogen Bond of methanolmethanol system and ethanol-ethanol system can be established and to know about the characters of both. The device of thi research use a set of computer which has been installed HyperChem 8.0 program for Windows 7. This program is used to determined the length, the angle of bond, and the torque bond of Hydrogen Bond in both of the systems until the minimum energy point was be founded. Based on the observation result data, for methanol-methanol system are obtained 2,3 Ǻ for the length and the energy is about 1,8414 kkal/mol, 112,4 θ for the angle bond and the energy is about 9.46454 kkal/mol, and 338,5 φ for the angle torsion and the energy is about 9.453914 kkal/mol. And for ethanol-ethanol system are obtained 2,8 Ǻ for the length and the energy is about 455.941282 kkal/mol, 121.9 θfor the angle bond and the energy is about 455.979291 kkal/mol, and 261.7 φfor the angle torsion and the energy is about 455.977901 kkal/mol. Keyword : hydrogen bond, molecule, radius, angle bond, torsion bond, minimum energy ABSTRAK Penelitian dilakukan dengan tujuan untuk mengetahui model persamaan ikatan hidrogen yang terjadi antara methanol-metanol dan antara etanol-etanol sehingga bisa diketahui sifat-sifatnya. Perangkat yang digunakan adalah perangkat komputer dengan aplikasi program HyperChem 8.0 for Windows 7. Program tersebut digunakan untuk menentukan panjang ikatan, sudut ikatan, dan sudut torsi yang terbentuk pada ikatan hidrogen di kedua molekul hingga titik energi minimum ditemukan. Berdasarkan data hasil pengamatan, untuk sistem metanol-metanol didapatkan panjang ikatan hidrogen sebesar 2,3 Ǻ dengan energi sebesar 1,8414 kkal/mol, sudut ikatan sebesar 112,4 θ dengan energi sebesar 9.46454 kkal/mol, dan sudut torsi sebesar 338,5 φ dengan energi sebesar 9.453914 kkal/mol. Sedangkan untuk sistem etanol-etanol didapatkan panjang ikatan hidrogen sebesar 2,8 Ǻ dengan energi sebesar 455.941282 kkal/mol, sudut ikatan sebesar 121.9 θ dengan energi sebesar 455.979291 kkal/mol, dan sudut torsi sebesar 261.7 φ dengan energi sebesar 455.977901 kkal/mol. Kata Kunci : ikatan hidrogen, molekul, jari-jari, sudut ikatan, torsi ikatan, energi minimum

The layered double hydroxide-based material features of Ca/Al have improved according to the adsorption capacity and structure stabilization by transforming into composite Ca/Al-graphite. The composite was synthesized by co-precipitation method, and the chemical structure was characterized using X-ray Diffraction (XRD), Fourier Transform Infra-red (FT-IR), Brunauer Emmet-Teller (BET) Surface Area, and Thermo-Gravimetry Differential Analyse (TG-DTA). The XRD analysis of Ca/Al-Graphite composite was noticed in 10.205°(003), 18.083°(012), 20.45°(004), 26.532°(002), 44.52°(101), 54.52°(004), and 77.38°(006). The TG-DTA analysis of the composite was noticed at 100°C as water molecule decomposition, 270°C as nitrate decomposition, and 700 and 760°C as graphite decomposition to the oxide form. BET surface area analysis of Ca/Al-Graphite composite achieved the highest surface area at 16.795 m2/g. According to the kinetic parameter, the adsorption of direct orange to composite follows the pseudo-second-order model. The isotherm parameter of direct orange adsorption onto the composite followed the Langmuir model and occurred spontaneously and endothermically. The regeneration study proved the composite effective in 3 cycles by adsorption percentage at the third cycle reached 73.559%.