Bond Measurement

ACoord provides automatic bond detection and interactive measurement tools.

Automatic Bond Detection

Bonds are automatically calculated based on:

• Interatomic distance — Atoms within threshold distance
• Element types — Covalent radius consideration
• Bonding criteria — Element-specific bonding radii

Bond Operations

Create Bond

1. Select two atoms (Ctrl/Cmd+click)
2. Right-click → Create Bond
3. Bond appears immediately

Delete Bond

1. Click on a bond to select it
2. Press Delete or Backspace
3. Or right-click → Delete Bond

Recalculate Bonds

• Click Calculate Bonds in the toolbar
• Or right-click in canvas → Calculate Bonds
• Bonds are recalculated based on current atom positions

Clear All Bonds

• Right-click in canvas → Clear All Bonds

Distance Measurement

Measure Distance

1. Select first atom (click)
2. Hold Ctrl/Cmd, select second atom
3. Distance displays in the Properties panel

Measure Angle

1. Select three atoms (Ctrl/Cmd+click)
2. Angle displays in the Properties panel
3. Angle is measured at the middle atom

Units

• Distance: Angstroms (Å)
• Angle: Degrees (°)

Common Bond Lengths

Reference values (Å):

Bond	Typical Length
C-C	1.54
C=C	1.34
C≡C	1.20
C-H	1.09
O-H	0.96
N-H	1.01
Si-O	1.61

Note: Actual values depend on chemical environment

Keyboard Shortcuts

Key	Action
Ctrl/Cmd+click	Add/remove atom from selection
Ctrl+A	Select all atoms
Ctrl+I	Invert selection
Delete/Backspace	Delete selected atoms/bonds