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State	Conformation	minimum conformation	conformer description	state description
1	1	yes	D*H	³Σ_g
2	1	yes	D*H	¹Σ_g

	hartrees
Energy at 0K	-578.872700
Energy at 298.15K	-578.871369
Nuclear repulsion energy	45.648188

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	1.136
Si2	0.000	0.000	-1.136

	Si1	Si2
Si1		2.2721
Si2	2.2721

Number	Element	Mulliken	CHELPG	AIM	ESP
1	Si	0.000
2	Si	0.000

All results from a given calculation for Si₂ (Silicon diatomic)

using model chemistry: mPW1PW91/cc-pVDZ

States and conformations

State 1 (³Σ_g)

State 2 (¹Σ_g)

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Calc. vs exp. Bad Vib. HF vs MP2 Bad scale factors Low excited states Oddities NaCN Is not linear FAQ Help Units Choose Units Energy Bond length Rotational Constant Moment of Inertia Dipole and Quadrupole Polarizability Explanations Hartree cm-1 Debye Credits Just show me Show me a calculated geometry Summary Using older interface Limit Basis sets Method options List Recent molecules Choose a few Molecules Number of atoms By heavy atoms Diatomics InChI Deuterated Dimers Geometry Point group Point group count Bonds types Isodesmic reactions Bad point group Multiple conformers, states Vibrations Big anharmonicity Energy Enthalpy at 0 Kelvin Similar molecules Similar Isomers Cis/trans Tautomers Multiple conformers, states Ions, Dipoles, etc. List Ions Ionization changes point group Dipole Quadrupole Polarizability Proton Affinities Index of CCCBDB Feedback Error form Wants
You are here: Calculated > Energy > Optimized > Energy

	hartrees
Energy at 0K	-578.825705
Energy at 298.15K	-578.824446
Nuclear repulsion energy	50.171986

<r²>	49.315
(<r²>)^1/2	7.022

<r²>	45.693
(<r²>)^1/2	6.760

All results from a given calculation for Si2 (Silicon diatomic)

using model chemistry: mPW1PW91/cc-pVDZ

States and conformations

State 1 (3Σg)

State 2 (1Σg)

All results from a given calculation for Si₂ (Silicon diatomic)

State 1 (³Σ_g)

State 2 (¹Σ_g)