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All Journal VALENSI Jurnal Ilmu Dasar POSITRON Jurnal Penelitian Fisika dan Aplikasinya (JPFA) Indonesian Journal of Chemistry Jurnal Fisika : Fisika Sains dan Aplikasinya Magnetic: Research Journal of Physics and It’s Application Abdi Geomedisains Jurnal Pengabdian Kepada Masyarakat (JPKM) Zadama: Jurnal Pengabdian Masyarakat Jurnal Pendidikan dan Pengabdian Masyarakat Molekul: Jurnal Ilmiah Kimia Jurna Beta Kimia Wahana Fisika : Jurnal Fisika dan Terapannya
Pingak, Redi Kristian
Universitas Nusa Cendana
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A Theoretical Study on Vibrational Energies of Molecular Hydrogen and Its Isotopes Using a Semi-classical Approximation Redi Kristian Pingak; Albert Zicko Johannes; Fidelis Nitti; Meksianis Zadrak Ndii
Indonesian Journal of Chemistry Vol 21, No 3 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.63294

Abstract

This study aims to apply a semi-classical approach using some analytically solvable potential functions to accurately compute the first ten pure vibrational energies of molecular hydrogen (H2) and its isotopes in their ground electronic states. This study also aims at comparing the accuracy of the potential functions within the framework of the semi-classical approximation. The performance of the approximation was investigated as a function of the molecular mass. In this approximation, the nuclei were assumed to move in a classical potential. The Bohr-Sommerfeld quantization rule was then applied to calculate the vibrational energies of the molecules numerically. The results indicated that the first vibrational transition frequencies (v1ß0) of all hydrogen isotopes were consistent with the experimental ones, with a minimum percentage error of 0.02% for ditritium (T2) molecule using the Modified-Rosen-Morse potential. It was also demonstrated that, in general, the Rosen-Morse and the Modified-Rosen-Morse potential functions were better in terms of calculating the vibrational energies of the molecules than Morse potential. Interestingly, the Morse potential was found to be better than the Manning-Rosen potential. Finally, the semi-classical approximation was found to perform better for heavier isotopes for all potentials applied in this study.
Ground State Energies of Helium-Like Ions Using a Simple Parameter-Free Matrix Method Redi Kristian Pingak; Atika Ahab; Utama Alan Deta
Indonesian Journal of Chemistry Vol 21, No 4 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.65737

Abstract

This study aims to use hydrogenic orbitals within an analytic and numeric parameter-free truncated-matrix method to solve the projected Schrödinger equation of some Helium-like ions (3 ≤ Z ≤ 10). We also derived a new analytical expression of the ion ground state energies, which was simple and accurate and improved the accuracy of the analytic calculation, numerically using Mathematica. The standard matrix method was applied, where the wave function of the ions was expanded in a finite number of eigenvectors comprising hydrogenic orbitals. The Hamiltonian of the systems was calculated using the wave function and diagonalized to obtain their ground state energies. The results showed that a simple analytic expression of the ground state energies of He-like ions was successfully derived. Although the analytic expression was derived without involving any variational parameter, it was reasonably accurate with a 0.12% error for Ne8+ ion. From this method, the accuracy of the analytic energies was also numerically improved to 0.10% error for Ne8+ ion. The results clearly showed that the energies obtained using this method were more accurate than the hydrogenic perturbation theory and the uncertainty principle-variational approach. In addition, for Z > 4, our results were more accurate than those from the geometrical model.
Quantum Anharmonic Oscillators: A Truncated Matrix Approach Redi Kristian Pingak; Albert Zicko Johannes; Minsyahril Bukit; Zakarias Seba Ngara
POSITRON Vol 11, No 1 (2021): Vol. 11 No. 1 Edition
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam, Univetsitas Tanjungpura

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (477.967 KB) | DOI: 10.26418/positron.v11i1.44369

Abstract

This study aims at implementing a truncated matrix approach based on harmonic oscillator eigenfunctions to calculate energy eigenvalues of anharmonic oscillators containing quadratic, quartic, sextic, octic, and decic anharmonicities. The accuracy of the matrix method is also tested. Using this method, the wave functions of the anharmonic oscillators were written as a linear combination of some finite number of harmonic oscillator basis states. Results showed that calculation with 100 basis states generated accurate energies of oscillators with relatively small coupling constants, with computation time less than 1 minute. Including more basis states could result in more correct digits. For instance, using 300 harmonic oscillator basis states in a simple Mathematica code in about 8 minutes, highly accurate energies of the oscillators were obtained for relatively small coupling constants, with up to 15 correct digits. Reasonable accuracy was also found for much larger coupling constants with at least three correct digits for some low lying energies of the oscillators reported in this study. Some of our results contained more correct digits than other results reported in the literature.
Pelatihan Penggunaan Perangkat TIK Untuk Peningkatan Mutu dan Kapasitas Pembelajaran di SMAN 1 Amfoang Tengah Albert Zicko Johannes; Redi K. Pingak; Jonshon Tarigan; Andreas Ch. Louk
Educativo: Jurnal Pendidikan Vol 1 No 2 (2022): Zadama: Jurnal Pengabdian Masyarakat
Publisher : PT. Marosk Zada Cemerlang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (381.932 KB) | DOI: 10.56248/zadama.v1i2.34

Abstract

Kecamatan Amfoang Tengah, Kabupaten Kupang merupakan wilayah dibangunnya Observatorium Nasional (OBNAS). Mayoritas penduduk di Amfoang tidak mengerti akan kepentingan keberadaan OBNAS dan tidak tahu tentang ilmu Astronomi. Hal ini karena masyarakat setempat masih kesusahan dalam mencari informasi terutama bila harus mengaksesnya dari internet. Sebagian besar kawasan ini masih belum terjangkau jaringan internet. SMAN 1 Amfoang Tengah yang menjadi pusat pembelajaran dan pendidikan bagi masyarakat di kawasan ini perlu mendapatkan akses jaringan internet melalui pengadaan sarana prasarana teknologi informasi dan komunikasi. Berdasarkan hal ini, maka program studi Fisika FST UNDANA bersedia menangani permasalahan tersebut melaluli kegiatan pengabdian pada masyarakat dengan cara memperkenalkan keberadaaan alat-alat pendukung sistem komunikasi internet seluler, mengajarkan tentang alat-alat tersebut, memperagakan penggunaan alat tersebut untuk mengakses sumber-sumber informasi dan menyumbangkan alat-alat tersebut untuk dapat dipakai seterusnya oleh pihak sekolah. Kegiatan pengabdian terselenggara dengan baik dan lancar dengan sedikit penyesuaian dari rencana awal (Pandemi COVID-19). Kegiatan ini mendapat sambutan positif. Pihak sekolah berterima kasih dengan kedatangan tim pengabdian serta peuyumbangan perangkat tersebut karena dapat membantu pihak sekolah dalam proses belajar mengajar untuk meningkatkan mutu dan kapasitas pembelajaran.
POTENSI ARANG AKTIF DARI KAYU POHON GAMAL (GLIRICIDIA SEPIUM) SEBAGAI MEDIA FILTRASI AIR Debi Lodo Ratu; Redi Kristian Pingak; Andreas Christian Louk; Jehunias Leonidas Tanesib; Minsyharil Bukit
Jurnal Fisika : Fisika Sains dan Aplikasinya Vol 7 No 2 (2022): Jurnal Fisika : Fisika Sains dan Aplikasinya
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/fisa.v7i2.9339

Abstract

Penelitian ini bertujuan untuk menurunkan tingkat salinitas air payau asal Lobohede Kabupaten Sabu Raijua dengan menggunakan arang aktif dari kayu pohon gamal sebagai media filtrasi. Kayu pohon gamal dikarbonisasi, kemudian aktivasi secara fisika dengan variasi waktu 1,1.5, dan 2 Jam dengan suhu tetap 8500C dan aktivasi secara kimia dengan variasi waktu perendaman 4,5, dan 6 jam dengan aktivator ZnCl2 kadar 25%. Pengujian arang aktif meliputi daya serap air, kadar abu, kadar air, kadar zat mudah menguap, dan kadar karbon terikat bertujuan untuk mengetahui potensi arang aktif sebagai media filtrasi air sesuai SNI 06-3730- 1995. Filtrasi air payau yang dilakukan dengan tiga variasi media filtrasi dengan susunan media tanpa arang aktif yakni (kerikil,pasir,dan kain kasa), penambahan arang aktif kayu gamal, penambahan arang aktif komersil. Salinitas awal air 0,7 ‰, salinitas air aktivasi secara kimia untuk ketiga sampel 0,6 ‰, aktivasi secara fisika( 1 jam 0,6 ‰, 1,5 dan 2 jam 0,5 ‰), sedangkan dengan penambahan arang aktif komersil 0,7 ‰. Berdasarakan perbandingan aktivasi secara fisika dan kimia dengan arang aktif komersil nilai salinitas terbaik terdapat pada aktivasi secara fisika waktu 1,5 dan 2 jam sebesar 0,5 ‰ karena pada pengujian kadar zat mudah menguap 25% dan kadar abu 10% sesuai dengan SNI 06-3730-1995.
Structural, Electronic, Elastic, and Optical Properties of Cubic BaLiX3 (X = F, Cl, Br, or I) Perovskites: An Ab-initio DFT Study Redi Kristian Pingak; Soukaina Bouhmaidi; Larbi Setti; Bartholomeus Pasangka; Bernandus Bernandus; Hadi Imam Sutaji; Fidelis Nitti; Meksianis Zadrak Ndii
Indonesian Journal of Chemistry Vol 23, No 3 (2023)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.83261

Abstract

This study reports for the first time the theoretical prediction of structural, electronic, elastic and optical properties of cubic BaLiCl3, BaLiBr3, and BaLiI3 perovskites. The corresponding properties of the well-known BaLiF3 are also theoretically investigated. Density Functional Theory (DFT) using the Generalized Gradient Approximation (GGA) was implemented within the Quantum Espresso package to investigate the properties of the perovskites. The results revealed that BaLiX3 (X = F, Cl, Br, and I) are in ionic crystal forms with optimized lattice parameters of 4.04, 4.90, 5.21, and 5.66 Å, respectively. The minor band gaps were found to be 6.62 eV (Γ→Γ), 4.29 eV (R→Γ), 3.50 eV (R→Γ), and 2.58 eV (R→Γ) for the respective compounds. The investigation of their elastic properties indicated that these perovskites are all mechanically stable, while only BaLiBr3 and BaLiI3 are malleable. Finally, the studied perovskites exhibit excellent optical properties, including low reflectivity and high absorption in the ultraviolet region. Hence, it is predicted that these perovskites are suitable for various optoelectronic applications involving absorption in the UV region. However, BaLiBr3 and BaLiI3 are more favorable than BaLiF3 and BaLiCl3 to be deposited as thin films due to their flexibility.
IDENTIFIKASI KANDUNGAN CaCO3 DALAM BATUAN KAPUR DI DESA MANULAI I MENGGUNAKAN METODE XRF DAN XRD Kristantia Mida Subah; Redi Kristian Pingak; Minsyahril Bukit; Albert Zicko Johannes
Jurnal Fisika : Fisika Sains dan Aplikasinya Vol 8 No 1 (2023): Jurnal Fisika : Fisika Sains dan Aplikasinya
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/fisa.v8i1.11825

Abstract

This study aims to determine the compounds contained in limestone, identify the content and crystal phase of CaCO3 in limestone and determine the effect of heating temperature on the CaCO3 crystal phase in limestone using XRF and XRD methods. XRF test results show that the compounds contained in limestone in Manulai I village are CaO, Nb2O5, Cr2O3, MoO3, In2O3, SnO2, Sb2O3, RuO4, dan Na2O and XRD test results showed that the crystal phase of CaCO3 at a temperature of 5500C to 7500C was in the form of calcite. In limestone calcined at different temperatures, the intensity increases, this can be interpreted that the higher the calcination temperature, the higher the crystallinity.
Penentuan Tingkat-Tingkat Energi Vibrasi Molekul Hidrogen Pada Keadaan Elektronik Dasar Menggunakan Potensial Morse Redi Kristian Pingak; Albert Zicko Johannes
Wahana Fisika Vol 5, No 1 (2020): June
Publisher : Universitas Pendidikan Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17509/wafi.v5i1.18614

Abstract

Pendekatan Born-Oppenheimer diterapkan untuk menghitung tingkat energi vibrasi keadaan dasar molekul hidrogen. Persamaan Schrodinger untuk inti atom diselesaikan dengan menggunakan metode semi-klasik, di mana inti atom diasumsikan bergerak secara klasik dalam sumur potensial dan energi vibrasi ditentukan dengan menerapkan aturan kuantisasi kuantum. Potensial yang digunakan pada penelitian adalah potensial Morse. Dalam penelitian ini, tingkat energi vibrasi dihitung dengan metode numerik, yaitu metode integrasi Simpson dan metode regula falsi. 15 Tingkat energi vibrasi dari molekul H2 diperoleh dan dibandingkan dengan data hasil eksperimen. Perbandingan ini mengindikasikan pendekatan yang digunakan pada penelitian ini memberikan hasil yang sangat akurat pada tingkat energi vibrasi yang relatif rendah (0≤n≤4), dengan kesalahan kurang dari 0,7%, dan untuk 5≤n≤8 dengan kesalahan maksimum 7,3%. Keakuratan menurun ketika tingkat energi vibrasi meningkat. Secara khusus, untuk n = 13 dan n = 14, kesalahan meningkat secara signifikan, menunjukkan gagalnya pendekatan ini untuk tingkat energi vibrasi yang relatif tinggi, khususnya untuk dua tingkat energi ini. Born-Oppenheimer approximation was applied to calculate vibrational energy levels of ground state of Hydrogen molecule. The Schrodinger equation for the nuclei was solved using a semi-classical method, in which the nuclei are assumed to move classically in a potential well and the vibrational energies are determined by applying the quantum mechanical quantization rules. Potential used in this research was the Morse potential. Here, vibrational energy levels of the molecule were calculated using numerical methods, i.e. Simpson integration method and false position method. 15 Vibrational energy levels of the H2 molecule were obtained and compared to the corresponding results from experiments. The comparison indicated that the approximation used in this research yielded very accurate results for relatively low vibrational levels (0≤n≤4), with errors being less than 0.7% and for 5≤n≤8 with maximum of 7.3% errors. The accuracy decreased as the vibrational levels increased, as expected. In particular, for n=13 and n=14, errors significantly increased, indicating the breakdown of the approximation for relatively high vibrational levels, in particular for these two energy levels.           Keywords: Hydrogen Molecule; Morse Potential; Born-Oppenheimer Approximation; Simpson Method; False Position Method
Uji Stabilitas Polymer Inclusion Membrane dari Polimer Pendukung PVC, Ekstraktan D2EHPA, dan Plasticizer Asam Oleat pada Kondisi Asam Rensini, William Antoni; Kadang, Luther; Lapailaka, Titus; Naat, Johnson Nune; Pingak, Redi Kristian; Kapitan, Origenes Boy; Nitti, Fidelis
Jurnal Beta Kimia Vol 4 No 1 (2024): Volume 4, Nomor 1: Mei 2024
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/jbk.v4i1.15351

Abstract

Polymer Inclusion Membrane (PIM) merupakan membran cair generasi terbaru untuk pemisahan berbagai jenis komponen kimia organik dan anorganik. Stabilitas PIM merupakan faktor yang sangat penting untuk efektivitas pemisahan yang berkelanjutan. Penelitian ini dilakukan untuk menyelidiki kestabilan PIM yang dibuat dari PVC sebagai polimer pendukung, D2EHPA sebagai ekstraktan, dan asam oleat (AO) sebagai plasticizer dalam HCl 2,5 M. Hasil penelitian menunjukkan komposisi PIM optimum adalah 50% PVC, 40% D2EHPA, dan 10% AO yang menunjukkan karakteristik fisik yang ideal seperti tipis, transparan, fleksibel dengan permukaan yang tidak berminyak. Hasil penelitian menunjukkan penurunan berat PIM yang direndam dalam HCl 2,5 M lebih kecil dibandingkan dengan penurunan berat PIM yang direndam dalam air selama 7 hari. Hasil ini menunjukkan bahwa PIM lebih stabil dalam kondisi asam dibandingkan dalam air (netral). Perbandingan karakteristik kimia PIM sebelum dan setelah uji stabilitas menunjukkan PIM yang direndam dalam air mengalami kehilangan fase cair selama proses uji stabilitas. Perbedaan ini terkonfirmasi melalui perbedaan karakteristik fisika PIM sebelum dan sesudah uji stabilitas. Secara keseluruhan, PIM dengan komposisi optimum 50% PVC, 40% D2EHPA, dan 10% AO disarankan untuk digunakan dalam pemisahan pada kondisi asam untuk mempertahankan stabilitas dan efisiensi pemisahannya.
Approximate Solution to the Schrödinger Equation of Exotic Doubly Muonic Helium-like Systems Using Hydrogenic-based Matrix Mechanics Pingak, Redi Kristian; Jacob, Johanes Eliaser; Bernandus, Bernandus; Johannes, Albert Zicko; Setiawan, Ely
Molekul Vol 19 No 1 (2024)
Publisher : Universitas Jenderal Soedirman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.jm.2024.19.1.11224

Abstract

The approximate solution to the Schrödinger equation of exotic doubly muonic helium-like systems has been obtained using a simple matrix method based on hydrogenic s-states. Each system considered consists of a positively charged nucleus surrounded by 2 negatively charged muons XZ+μ-μ- (2 Z 36). The present work aims to obtain approximate ground-state energies of the systems and to decompose the energies in terms of the basis states used. Here, the wave function was expressed as a linear combination of 15 eigenfunctions, each written as the product of two hydrogenic s-states. The elements of the Hamiltonian matrix were calculated and finally, the energy eigenvalue equation was numerically solved to obtain the ground-state energies of the systems with their corresponding eigenvectors. From the results, ground-state energies of all systems were in agreement with others from the literature, with percentage differences between 0.03% and 2.05%. The analysis of the probability amplitudes from the eigenvectors showed that the 1s1s state made the largest contribution to the ground state energies of the systems, approaching 90.99%, 96.98% and 98.54% for He2+μ-μ- , Li3+μ-μ- , and Be4+μ-μ- , respectively. Keywords: Doubly muonic helium-like systems, ground state energy, hydrogenic basis states, matrix mechanics, Schrödinger equation
Co-Authors Abdul Wahid Albert Z. Johannes Ali Warsito Amaral, Madalena A. Andreas Ch. Louk Andreas Christian Louk Andreas Christian Louk Anggi Arni Biha Atika Ahab Atika S. Ahab Bartholomeus Pasangka Bernandus Bernandus Bernandus Bernandus Bernandus Bernandus, Bernandus Bukit, Minsyahril Candra Satrio Umbu Luba Christine Mbiliyora Debi Lodo Ratu Elisabeth Boimau Eltra E. Barus Fidelis Nitti Gerda Pandu Godensius Tematur Hadi I Sutaji Hery L. Sianturi Intan M.P. Dewi Intan Riani Solo Jacob, Johanes Eliaser Johannes, Albert Z. Johannes, Albert Zicko Johnson N Naat Jonshon Tarigan Kapitan, Origenes Boy Kolmate, Rosara Kristantia Mida Subah Laalobang, Sriwiana Lapailaka, Titus Lapono, Laura Anastasi Seseragi Larbi Setti Laura A. S. Lapono Lemau, Alexia Leonardus Nengga Lerrick, Reinner Ishaq Luther Kadang Magdalena M. Y. Missa Mamut, Anastasia Maria Lurumutin Umrisu Maria S. Mali Marselinus E. Dandara Maunino, Mariani R. Medi, Yovilia Meksianis Zadrak Ndii Minsyahril Bukit Minsyahril Bukit Minsyahril Bukit Minsyharil Bukit Modhe, Katarina Ndii, Meksianis Z Pasangka, Bartholomeus Refli, Refli Rensini, William Antoni Rosara Kolmate Roswita T. Saman Setiawan, Ely Severianus Wunda Sherlly Ledoh Siu, Kristina Soukaina Bouhmaidi Sutaji, Hadi Imam Tanesib, Jehunias Leonidas Tarigan, Jhonson Tarigan, Jonshon Utama Alan Deta Warsito, Ali Yasinta Kresnawati Yuditha Ignasia Bete Z. Johannes, Albert Zakarias Seba Ngara