MVC сложные View Models

Не могу победить ошибку при запуске View RequestCreate.cshtml:

The model item passed into the dictionary is of type 'SDS.WebUI.Models.RequestEditViewModel', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable`1[SDS.WebUI.Models.RequestDetailListViewModel]'.

Что не так?

Имеется:

View Models:

public class RequestEditViewModel  
{  
     public int RequestID { get; set; }
     public string Name { get; set; }
     public virtual IEnumerable<RequestDetailListViewModel> RequestDetails { get; set; }
}
public class RequestDetailListViewModel
{
        [Key]
        public int RequestDetailID { get; set; }
        public int RequestID { get; set; }
        [ForeignKey("RequestID")]
        public virtual Request Request { get; set; }
        public string DetailName { get; set; }
  }

Controller:

public ActionResult RequestCreate()
{
    RequestEditViewModel mVm = new RequestEditViewModel {};
    return View(mVm);
}

Views:

RequestCreate.cshtml

@model SDS.WebUI.Models.RequestEditViewModel
@using (Html.BeginForm())
{
    .....
     Html.Partial("RequestDetailPartialView");
     //Html.Partial("RequestDetailPartialView",   @Model.RequestDetails.AsEnumerable());
     //Html.RenderPartial("RequestDetailPartialView", null);
}

RequestDetailPartialView.cshtml

@model IEnumerable<SDS.WebUI.Models.RequestDetailListViewModel>
@{
    var grid = Html.DevExpress().GridView(settings =>
    {
        settings.Name = "GridRequestDetail";
        settings.KeyFieldName = "RequestDetailID";
        .....
        settings.Columns.Add("RequestDetailID");
        settings.Columns.Add("DetailName");
   });
}
@grid.Bind(Model).GetHtml()