# SN2 Reaction Mechanism A chemistry diagram showing the bimolecular nucleophilic substitution (SN2) mechanism between hydroxide ion and methyl bromide. Demonstrates molecular structure rendering, electron movement arrows, transition state notation, and reaction energy profiles. ## Key Patterns Used - **Molecular structures**: Ball-and-stick style atoms with bonds - **Electron movement**: Curved arrows showing nucleophilic attack - **Transition state**: Bracketed pentacoordinate intermediate with partial charges - **Stereochemistry**: Wedge/dash bonds showing 3D configuration - **Energy profile**: Potential energy vs reaction coordinate plot - **Annotation boxes**: Key features and mechanistic notes ## Diagram Type This is a **chemistry mechanism diagram** with: - **Molecular rendering**: Atoms as colored circles with element symbols - **Bond notation**: Solid, wedge, dash, and partial (dashed) bonds - **Reaction arrows**: Curved for electron movement, straight for reaction progress - **Energy landscape**: Quantitative energy profile below mechanism ## Molecular Structure Elements ### Atom Rendering ```xml C O H Br ``` ```css .carbon { fill: #2C2C2A; } .hydrogen { fill: #F1EFE8; stroke: #888780; stroke-width: 1; } .oxygen { fill: #E24B4A; } .bromine { fill: #993C1D; } .nitrogen { fill: #378ADD; } /* for other reactions */ ``` ### Bond Types ```xml ``` ```css .bond { stroke: var(--text-primary); stroke-width: 2.5; fill: none; stroke-linecap: round; } .bond-thin { stroke: var(--text-primary); stroke-width: 1.5; fill: none; } .bond-partial { stroke: var(--text-primary); stroke-width: 2; fill: none; stroke-dasharray: 4 3; } .bond-wedge { fill: var(--text-primary); stroke: none; } .bond-dash { stroke: var(--text-primary); stroke-width: 2; fill: none; stroke-dasharray: 2 2; } ``` ### Lone Pairs and Charges ```xml ⊖ δ⁻ δ⁺ ``` ```css .charge { font-family: "Times New Roman", Georgia, serif; font-size: 12px; } .partial { font-family: "Times New Roman", Georgia, serif; font-size: 11px; font-style: italic; } ``` ### Curved Arrow (Electron Movement) ```xml ``` ```css .arrow-curved { stroke: #534AB7; stroke-width: 2; fill: none; } .arrow-fill { fill: #534AB7; } ``` ### Transition State Brackets ```xml ‡ ``` ```css .ts-bracket { stroke: var(--text-primary); stroke-width: 1.5; fill: none; } ``` ## Energy Profile Diagram ### Axes ```xml Potential Energy Reaction Coordinate ``` ### Energy Curve ```xml ``` ```css .energy-curve { stroke: #534AB7; stroke-width: 2.5; fill: none; } .energy-fill { fill: rgba(83, 74, 183, 0.1); } ``` ### Energy Levels and Annotations ```xml Reactants Transition State [‡] Ea ``` ```css .energy-level { stroke: var(--text-secondary); stroke-width: 1; stroke-dasharray: 4 2; fill: none; } .delta-arrow { stroke: #3B6D11; stroke-width: 1.5; fill: none; } .delta-fill { fill: #3B6D11; } ``` ## Chemistry Text Styles ```css /* Chemistry notation (serif font for formulas) */ .chem { font-family: "Times New Roman", Georgia, serif; font-size: 16px; fill: var(--text-primary); } .chem-sm { font-family: "Times New Roman", Georgia, serif; font-size: 12px; fill: var(--text-primary); } .chem-lg { font-family: "Times New Roman", Georgia, serif; font-size: 18px; fill: var(--text-primary); } ``` ## Subscript/Superscript in SVG ```xml Ea OH⁻ CH₃Br ``` ## Color Coding | Element | Color | Hex | |---------|-------|-----| | Carbon | Dark gray | #2C2C2A | | Hydrogen | Light cream | #F1EFE8 | | Oxygen | Red | #E24B4A | | Bromine | Brown | #993C1D | | Nitrogen | Blue | #378ADD | | Electron arrows | Purple | #534AB7 | | Positive charge | Green | #3B6D11 | | Negative charge | Red | #A32D2D | ## Layout Notes - **ViewBox**: 800×680 (landscape for mechanism + energy profile) - **Mechanism section**: y=60-300, showing reactants → TS → products - **Energy profile**: y=320-630, with axes and curve - **Atom sizes**: C/O/Br ~12-16px radius, H ~7-8px radius - **Bond lengths**: ~25-40px between atom centers - **Spacing**: ~140px between mechanism stages ## When to Use This Pattern Use this diagram style for: - Organic reaction mechanisms (SN1, SN2, E1, E2, additions, eliminations) - Reaction energy profiles and kinetics - Stereochemistry illustrations - Enzyme mechanism diagrams - Transition state theory visualization - Any chemistry concept requiring molecular structures