# SciDart Skills - Interactive 3D Nanoscience & Spectroscopy Courses Index

Welcome to **SciDart Skills**, the premier interactive virtual laboratory and educational platform for advanced materials science, surface characterization, and analytical spectroscopy.

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## 1. Atomic Force Microscopy (AFM) & Nanometrology
- **URL**: `https://skills.scidart.com/#/course/atomic-force-microscopy`
- **Category**: Surface Characterization & Nanometrology
- **Level**: Intermediate - Advanced
- **Duration**: 3.5 Hours
- **3D Virtual Lab**: Interactive 3D AFM Cantilever Simulator with Laser Deflection, Photodiode PID Feedback, and Surface Topography Scanning (Nanoparticles, DNA Plasmid, Graphene Steps, Block Copolymers).
- **Key Concepts & Topics**:
  - Cantilever spring constants (k) and resonance frequencies (f0).
  - Tap-mode & contact-mode Lennard-Jones interatomic force potentials (van der Waals attraction & Pauli repulsion).
  - Optical lever amplification with 4-quadrant position-sensitive photodiode (PSPD).
  - Proportional-Integral-Derivative (PID) feedback loop tuning to prevent tip crash and minimize error signals.
  - Quantitative surface roughness parameters (RMS roughness Sq, Average roughness Sa, Peak-to-Valley Sz).
  - Tip radius convolution effects and artifact deconvolution.

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## 2. Single Crystal X-Ray Diffraction (SC-XRD) & 3D Crystallography
- **URL**: `https://skills.scidart.com/#/course/single-crystal-xrd`
- **Category**: Crystallography & Structural Chemistry
- **Level**: Intermediate - Advanced
- **Duration**: 4.0 Hours
- **3D Virtual Lab**: 3D Single Crystal Diffractometer with 4-Circle Goniometer Rotation (Phi, Omega, Two-Theta), Monochromatic X-Ray Beam, NaCl Unit Cell Lattice, and Real-Time PILATUS 2D Area Detector Bragg Spot Reflections.
- **Key Concepts & Topics**:
  - Bragg's Law: $n\lambda = 2d \sin\theta$ for constructive X-ray wave interference.
  - Reciprocal lattice geometry and Ewald sphere intersection condition ($\vec{k} - \vec{k}_0 = \vec{G}_{hkl}$).
  - 4-Circle Goniometer orientation angles ($\phi$, $\chi$, $\omega$, $2\theta$).
  - PILATUS pixel array detector frame integration and Miller index $(hkl)$ indexing.
  - Atomic form factors $f_j(\theta)$ and structure factor $F(hkl) = \sum f_j \exp[2\pi i (hx_j + ky_j + lz_j)]$.
  - 3D Fourier electron density synthesis $\rho(x,y,z)$ for small molecule structure solution.

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## 3. UV-Vis Absorption Spectroscopy & Semiconductor Optics
- **URL**: `https://skills.scidart.com/#/course/uv-vis-spectroscopy`
- **Category**: Photophysics & Optical Characterization
- **Level**: Beginner - Intermediate
- **Duration**: 2.5 Hours
- **3D Virtual Lab**: 3D Dual-Beam Spectrophotometer with Deuterium/Tungsten Light Sources, Monochromator Diffraction Grating, Sample/Reference Quartz Cuvette Compartments, Photomultiplier Tube (PMT) Detector, and Live Spectrum Graph.
- **Key Concepts & Topics**:
  - Beer-Lambert Law: $A = \epsilon \cdot c \cdot l = -\log_{10}(I/I_0)$.
  - Electronic transitions: $\pi \to \pi^*$, $n \to \pi^*$, and d-d metal complex transitions.
  - Chromophores, auxochromes, bathochromic (red) shifts, and hypsochromic (blue) shifts.
  - Tauc Plot analysis for optical band gap ($E_g$) estimation in direct and indirect semiconductors: $(\alpha h\nu)^{1/\gamma} = B(h\nu - E_g)$.
  - Quantum confinement effect in CdSe quantum dots shifting absorption onset wavelength.