From 15b39ca8f5ae49f5c08bd35621ac13c14ea05367 Mon Sep 17 00:00:00 2001
From: Nuwan Yapa <yapanuwan@gmail.com>
Date: Thu, 4 Jun 2026 17:52:17 -0400
Subject: [PATCH] Temp commit

---
 calculations/He_cluster.jl | 38 ++++++++++++++++++++++++++++++++++++++
 ho_space_3body_V3b.jl      | 31 +++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+)
 create mode 100644 calculations/He_cluster.jl
 create mode 100644 ho_space_3body_V3b.jl

diff --git a/calculations/He_cluster.jl b/calculations/He_cluster.jl
new file mode 100644
index 0000000..aa55b88
--- /dev/null
+++ b/calculations/He_cluster.jl
@@ -0,0 +1,38 @@
+using Arpack
+include("../ho_basis.jl")
+
+coord_system = jacobi
+atol = 10 ^ -5
+maxevals = 10 ^ 5
+
+Λ = 0
+m = 1.0 / 43.281307
+V_of_r(r) = -1.2343566 * exp(-r^2 / 100)
+
+# three-body potential V3b = V3b_of_r(r12) * V3b_of_r(r23) * V3b_of_r(r31)
+V3b_of_r(r) = 0.43 * exp(-(2/3) * r^2 / 100)
+
+E_max = 30
+μω_global = 0.1
+
+μ1ω1 = μω_global * 1/2
+basis = ho_basis_2B(E_max, Λ)
+
+V1_elem(l, n1, n2) = V_numerical(V3b_of_r, l, n1, n2; μω_gen=μ1ω1, atol=atol, maxevals=maxevals)
+@time "V1" V1 = get_sp_V_matrix(V1_elem, basis.n1s, basis.l1s, [basis.n2s, basis.l2s]; dtype=ComplexF64, E_max=basis.E_max)
+
+V_relative_elem(l, n1, n2) = V_numerical(V3b_of_r, l, n1, n2; μω_gen=μω_global, atol=atol, maxevals=maxevals)
+V_relative_cache = prealloc_V_cache(basis.E_max, ComplexF64)
+
+V_relative_1 = get_sp_V_matrix(V_relative_elem, basis.n1s, basis.l1s, [basis.n2s, basis.l2s]; dtype=ComplexF64, cache=V_relative_cache)
+V_relative_2 = get_sp_V_matrix(V_relative_elem, basis.n2s, basis.l2s, [basis.n1s, basis.l1s]; dtype=ComplexF64, cache=V_relative_cache)
+@time "V_relative" V_relative = V_relative_1 * V_relative_2 # commutative?
+U = Moshinsky_transform(basis)
+@time "V2" V2 =  transpose(U) * V_relative * U
+
+@time "V3b" V3b = V2 * V1 # commutative?
+
+H = get_3b_H_matrix(coord_system, V_of_r, μω_global, E_max, Λ, m) + V3b
+
+@time "Eigenvalues" evals, _ = eigs(H, nev=3, ncv=30, which=:SR, maxiter=5000, tol=1e-5, ritzvec=false, check=1)
+display(evals)
diff --git a/ho_space_3body_V3b.jl b/ho_space_3body_V3b.jl
new file mode 100644
index 0000000..2e29e44
--- /dev/null
+++ b/ho_space_3body_V3b.jl
@@ -0,0 +1,31 @@
+using Arpack
+include("ho_basis.jl")
+
+coord_system = src
+atol = 10 ^ -5
+maxevals = 10 ^ 5
+
+Λ = 0
+m = 1.0
+V_of_r(r) = -2 * exp(-r^2 / 4)
+
+# three-body potential V3b = V3b_of_r(r12) * V3b_of_r(r23) * V3b_of_r(r31)
+V3b_of_r(r) = -1 * exp(-r^2 / 4)
+
+E_max = 40
+μω_global = 0.3
+
+# compute three-body potential matrix elements
+μω = μω_global * 2
+basis = ho_basis_2B(E_max, Λ)
+V3b_elem(l, n1, n2) = V_numerical(V3b_of_r, l, n1, n2; μω_gen=μω, atol=atol, maxevals=maxevals)
+V_cache = prealloc_V_cache(basis.E_max, ComplexF64)
+@time "V1" V1 = get_sp_V_matrix(V3b_elem, basis.n1s, basis.l1s, [basis.n2s, basis.l2s]; dtype=ComplexF64, cache=V_cache)
+@time "V2" V2 = get_sp_V_matrix(V3b_elem, basis.n2s, basis.l2s, [basis.n1s, basis.l1s]; dtype=ComplexF64, cache=V_cache)
+@time "V12" V12 = get_src_V12_matrix(V3b_of_r, basis, μω_global; atol=atol, maxevals=maxevals)
+@time "V3b" V3b = (V1 * V2) * V12 # commutative?
+
+H = get_3b_H_matrix(coord_system, V_of_r, μω_global, E_max, Λ, m) + V3b
+
+@time "Eigenvalues" evals, _ = eigs(H, nev=3, ncv=30, which=:SR, maxiter=5000, tol=1e-5, ritzvec=false, check=1)
+display(evals)