Drawing Basics

Drawing Basics

This page introduces the basic tools for placing and changing chemical structures on a ChemDraft page.

ChemDraft draws into a document page rather than an unbounded canvas. Start with the Selection Tool, then choose a structure tool from the Main Toolbar or a floating palette. A tool remains active until you choose another one; Esc is shown in the tool hints as the way to leave an active drawing interaction.

A reliable first workflow

1. Choose Single Bond and click empty space to begin a structure, or click an existing atom to extend it.
2. Drag from an atom when you need to aim the new bond. During a drag, bond, ring, and template placement snaps to absolute 15° angles. Hold Option on macOS or Alt on Windows for a free angle.
3. Switch to the Atom Label Tool to edit an atom, or use the Text Tool for ordinary annotations.
4. Use the Selection Tool to move an object or drag a region around objects. The Lasso Selection tool can subtract with Option on macOS or Alt on Windows.
5. Save from File > Save. Each committed drawing action is an undoable document change.

Single bonds, wedges, hashed wedges, dashed bonds, bold bonds, chains, rings, labels, and text are separate tools. The bond button’s flyout is the quickest route to the bond variants. A long press on a toolbar item opens its flyout; a normal click uses its primary tool.

Placement and snapping

For a straight chain, its first bond follows the same 15° aiming rule. The Flexible Chain tool deliberately follows the pointer path instead, without angle snapping. Bond drags normally preserve the standard bond length; after the custom-length breakaway, the length follows the drag and the app shows an Å readout. A placement that would end beyond the page is shortened to the page edge along the chosen angle.

Clicking an existing atom uses that atom as the target. Dropping a dragged bond on an atom in another molecule joins the two molecule objects and creates the bond across their former boundary. ChemDraft does not use placement convenience as permission to make an impossible structure: when a ring or attachment would overfill a covalent valence, it refuses that attachment and explains why in the status line. See Rings and Chains and Chemistry Guarantees.

Selecting, moving, and deleting

The Selection Tool clicks objects, moves them by dragging, and selects regions by dragging on empty canvas. The Eraser Tool can click or drag over objects; its marquee deletes the objects it touches. Backspace and Delete also delete the selection or a hovered native atom or bond. On a labeled atom, the first Delete/Backspace removes the label and keeps the skeletal atom and its bonds; a second press deletes the atom.

Use Edit > Undo if a placement was not what you intended. Standard Undo and Redo shortcuts are listed in Keyboard Shortcuts. The visible page, ruler units, and crosshairs are documented in Documents, Pages, and Tabs.

A few useful distinctions

• A dashed single bond is chemical notation for a dative or partial interaction, not merely a decorative line. See Charges, Radicals, and Dative Bonds.
• A typed atom label can be literal chemistry rather than an ordinary skeletal atom. See Atoms and Labels.
• Wedge and hashed bonds convey stereochemical display. See Bonds and Stereochemistry.
• Arrows, brackets, and mechanism marks are covered in Arrows and Mechanisms.

Next

• Atoms and Labels
• Selection and Editing
• Toolbars and Palettes