FermionWavefunction<TIndex> Constructors

Reference

Definition

Namespace:: Microsoft.Quantum.Chemistry.Fermion

Assembly:: Microsoft.Quantum.Chemistry.DataModel.dll

Package:: Microsoft.Quantum.Chemistry.DataModel v0.25.218240

Important

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Overloads

FermionWavefunction<TIndex>(IEnumerable<ValueTuple<TIndex[],Double>>)	Constructs a sparse multi-reference wave function
FermionWavefunction<TIndex>(IEnumerable<TIndex>)	Constructs a single-reference wave function. This is treated as sparse multi-reference wave function with only one term.
FermionWavefunction<TIndex>(IEnumerable<TIndex>, IEnumerable<ValueTuple<TIndex[],Double>>)	Constructs a unitary coupled-cluster wave function represented by a unitary coupled-cluster operator acting on a single-reference state.

FermionWavefunction<TIndex>(IEnumerable<ValueTuple<TIndex[],Double>>)

Constructs a sparse multi-reference wave function

public FermionWavefunction (System.Collections.Generic.IEnumerable<(TIndex[], double)> terms);

new Microsoft.Quantum.Chemistry.Fermion.FermionWavefunction<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)> : seq<ValueTuple<'Index[], double>> -> Microsoft.Quantum.Chemistry.Fermion.FermionWavefunction<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)>

Public Sub New (terms As IEnumerable(Of ValueTuple(Of TIndex(), Double)))

Parameters

terms: IEnumerable<ValueTuple<TIndex[],Double>>

List of tuples specifying an unnormalized superposition of basis states. The first item of each tuple is a list of indices to the creation operator sequence acting on the vacuum state. The second item of each tuple is the unnormalized amplitude of the specified basis state.

Examples

Create a list of tuples where the first item of each tuple are indices to the creation operators acting on the vacuum state, and the second item is the coefficient of that basis state. Next, create a fermion wavefunction object that represents the superposition.

var superposition = new[] 
{
    (new[] {1, 2, 6}, 0.1),
    (new[] {2, 1, 5}, -0.2) 
};
var wavefunction = new FermionWavefunction<int>(superposition);

Applies to

FermionWavefunction<TIndex>(IEnumerable<TIndex>)

Constructs a single-reference wave function. This is treated as sparse multi-reference wave function with only one term.

public FermionWavefunction (System.Collections.Generic.IEnumerable<TIndex> term);

new Microsoft.Quantum.Chemistry.Fermion.FermionWavefunction<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)> : seq<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)> -> Microsoft.Quantum.Chemistry.Fermion.FermionWavefunction<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)>

Public Sub New (term As IEnumerable(Of TIndex))

Parameters

term: IEnumerable<TIndex>

Sequence of indices of creation operators acting on the vacuum state.

Examples

Create a list of indices of the creation operators, then Convert the list of indices to a FermionWavefunction instance.

var indices = new[] { 1, 2, 6 };
var wavefunction = new FermionWavefunction<int>(indices);

Applies to

FermionWavefunction<TIndex>(IEnumerable<TIndex>, IEnumerable<ValueTuple<TIndex[],Double>>)

Constructs a unitary coupled-cluster wave function represented by a unitary coupled-cluster operator acting on a single-reference state.

public FermionWavefunction (System.Collections.Generic.IEnumerable<TIndex> reference, System.Collections.Generic.IEnumerable<(TIndex[], double)> excitations);

new Microsoft.Quantum.Chemistry.Fermion.FermionWavefunction<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)> : seq<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)> * seq<ValueTuple<'Index[], double>> -> Microsoft.Quantum.Chemistry.Fermion.FermionWavefunction<'Index (requires 'Index :> IEquatable<'Index> and 'Index :> IComparable<'Index>)>

Public Sub New (reference As IEnumerable(Of TIndex), excitations As IEnumerable(Of ValueTuple(Of TIndex(), Double)))

Parameters

reference: IEnumerable<TIndex>

Sequence of indices of creation operators acting on the vacuum state.

excitations: IEnumerable<ValueTuple<TIndex[],Double>>

Examples

Create a list of indices of the creation operators for the single-reference state.

Then create a list describing the cluster operator. The first half of each list of integers will be associated with the creation operators, and the second half with the annihilation operators.

Finally, create a fermion wavefunction object that represents the unitary coupled-cluster wavefunction. It is assumed implicity that the exponent of the unitary coupled-cluster operator is the cluster operator minus its Hermitian conjugate.

var reference = new[] { 1, 2 };
var clusterOperator = new[]
{
    (new [] {0, 1}, 0.123),
    (new [] {0, 3, 1, 2}, 0.456),
    (new [] {3, 2, 1, 0}, 0.789)
};
var wavefunction = new FermionWavefunction<int>(reference, clusterOperator);

Applies to